A45 AMG: One step at a time
19 February 2015, 10:20 PM
#31
Interesting choice Shaun, look forward to seeing how it progresses and what you can get out of it.
Personally never been mad on mercs, that was until my brother-in-law got a c63 amg coupe last year through work. Wow what a noise that thing made!
How's yours on fuel currently?
Paul
Personally never been mad on mercs, that was until my brother-in-law got a c63 amg coupe last year through work. Wow what a noise that thing made!
How's yours on fuel currently?
Paul
20 February 2015, 07:41 AM
#32
Scooby Regular
Thread Starter
20 February 2015, 07:55 AM
#33
Scooby Regular
Thread Starter
lordharding,
I'd probably consider ticking all of those boxes.
bioforger,
I couldn't justify it either to begin with...... I work flaming hard and it's no good me saving cash every month and never spending it. So I thought **** it!
The only trouble, now that I've accepted blowing 40g's for the weekend burner is fine, I'm now thinking "Well.... 40k's not too bad.... I'll push the boat out a bit more next time and get a C63 AMG".
Paul,
I never considered a MB, until I saw the A45 with the aero kit, and took one for a test drive. As soon as I drove one nothing else mattered.... I just had to have one. That sounds over the top, but that's what happened and how I felt. I haven't felt like that after initially driving a car, for many years.
I can't believe how economical it is. I went down to London the other day. 190mile round trip and it averaged 36.2 mpg. Granted, this was a majority of mway driving, but still.
On my mixed use (A, B, rural and urban - taking it steady and giving it some) it averages around 30 mpg.
I'd probably consider ticking all of those boxes.
bioforger,
I couldn't justify it either to begin with...... I work flaming hard and it's no good me saving cash every month and never spending it. So I thought **** it!
The only trouble, now that I've accepted blowing 40g's for the weekend burner is fine, I'm now thinking "Well.... 40k's not too bad.... I'll push the boat out a bit more next time and get a C63 AMG".
Paul,
I never considered a MB, until I saw the A45 with the aero kit, and took one for a test drive. As soon as I drove one nothing else mattered.... I just had to have one. That sounds over the top, but that's what happened and how I felt. I haven't felt like that after initially driving a car, for many years.
I can't believe how economical it is. I went down to London the other day. 190mile round trip and it averaged 36.2 mpg.
Granted, this was a majority of mway driving, but still. On my mixed use (A, B, rural and urban - taking it steady and giving it some) it averages around 30 mpg.
20 February 2015, 03:13 PM
#34
That's not bad return for a performance car.
My bro-in-law managed under 20mpg in his c63 on his commute to brackley, very thirsty and he didnt drive like a loon (all the time).
Anyway if it's a weekend car who cares about mpg?!
My bro-in-law managed under 20mpg in his c63 on his commute to brackley, very thirsty and he didnt drive like a loon (all the time).
Anyway if it's a weekend car who cares about mpg?!
21 February 2015, 04:24 PM
#35
Scooby Regular
Thread Starter
Right then guys…… this is where it all starts! Well, after we cover this preamble.
Preamble
First off I would like to underline a key point. I’m not suggesting at the moment that I’m going to find out anything new or revolutionary. A lot of the initial steps I’ll be taking will undoubtedly be exactly the same as others have done before me. But I need to do it “one step at a time”, because that’s the way you learn using a pragmatic approach.
The difference with this project (I suspect) will be to go into as much detail as possible, within the context of what has been or planned to be done.
If you’re looking for “just” power graphs and peak figure talk….. whilst you’ll find that information here, this is really not what my project thread will be about - there is a lot more to modifications than just using these two elements as reference.
If I have one “mission” in life, that “mission” is to keep highlighting that on their own, peak figures mean diddly squat. If you just skim read this project, focussing on peak values and comparing those with other peak values (from others achievements), you are in my opinion, missing valuable context. Peak figures do not make for a quick car, and they certainly don’t tell you what you really need to appreciate. Peak figures are for the pub - and the next round won’t be on me!
As one community member said in comment to the introduction post, “That's a lot of rice to consume right there!”. That’s the way I roll. So you best get your empty plate ready, grab some salt and pepper, tuck your napkin in under your chin and prepare yourself for a mammoth “eat as much as you like” experience!!
I want to understand the detail of why and how, which will hopefully allow us all to understand how things could be improved and what is potentially looked at next in the journey.
First thing is to state that Litchfield Motors will be key company I’ll be working with at this stage.
Why choose Litchfield?
You may be thinking that Litchfield have no real presence in the MB tuning scene at present (although that does not mean they have not been developing products for the MB marque), so why would I be working with them when there are other well established MB tuners in this scene.
I’m not going to go into a full on promo speech about Litchfield. Their past creations like their Type 20, Type 25, Time Attack winning Type 25 Race Car and their recent GTR and BMW developments tell you an impressive story. Let alone the intrinsic involvement they have had with my own “Project Cars”, which have had their own “notoriety” within the Subaru community over the past 10 yrs.
What is certainly within context of this project is:
I’ve worked with Litchfield on a number of projects before (for well over 10yrs), albeit within the Subaru scene. They have proved to me without doubt, that they are absolutely committed to achieving excellence, having a vast amount of tuning and development experience…. with their key goal to always create and sell packages that make a car very quick on the road, delivering what the customer really wants - even if the customer doesn’t always know what they want. They are absolutely passionate about this.
Litchfield also understand, support and appreciate the benefits that an “open project” like this can provide…… not all tuning companies “get” this kind of approach and would rather keep things “hush hush” - I’m all about sharing as much information as I can with the community (it’s what really drives me to do this kind of project work) - Litchfield wholeheartedly support this approach.
Litchfield also have a well established technical partner network which includes Turbo Dynamics, AET Turbos, EcuTEK, COBB, Syvecs, Whiteline, Bilstein, Eibach, Miltek, Akrapovic, Forge, Alcon etc. This is a massive plus to me and this project, as these companies are some of the “big hitters” in the industry. This will only help support any proposed development in my opinion.
Last but by no means least is the expertise/facilities that Litchfield possess “in house”. They have a large workshop facility which includes a multitude of ramps, alignment rigs, engine/gearbox build rooms, engine dyno and cell, chassis dyno and cell, fabrication facilities (i.e. they can produce their own exhaust systems in-house for prototyping). Litchfields also have a vast amount of engine calibration tools and expertise, to develop “methods” and utilise those “methods” to maximise the potential that ECU mapping (which is also completed on-site by Litchfield) can present.
With a number of the projects that either Litchfield have commissioned themselves, or supported those commissioned by others, they have built a massive amount of knowledge and expertise. They don’t only develop and deliver great road car packages, but they are also able to produce packages that do the business in competition on track.
Having the opportunity to work with a company that possess these facilities, level of experience and passion, should hopefully benefit the progression of this project.
Performance measurement and tuning aids - Rolling Road Overview
Perhaps the single biggest bone of contention is how I would decide to measure/test for any increases (and of course decreases) in power, when looking at engine modifications. Several ways exist, namely use of a Rolling Road, Engine Dyno, Performance Meters and the regularly used “**** dyno” (for those that are not familiar with this, it is the term given to the “just driven my car and it feels so much quicker now…. It must be 400bhp”).
For the purpose of engine based modifications, stats will be attained by use of a Rolling Road, coupled with real driving feedback on the road.
Even though we may all agree that various rolling roads will give different readings, and the arguments that RR figures at X are incorrect and RR figures at Y are correct, is meaningless to a degree.
Although many conditions even on the same rolling road can cause changes in figures, we need something we can use to compare with accuracy and repeatability. Obviously the more conditions you can stabilise the more your figures will be representative.
Now, before I explain things further it’s probably worth me stating one thing here and now. I’m a self confessed “dyno queen”. At a guess, I suspect I have had well in excess of 500 runs on various dyno’s over the years (I wouldn’t actually be surprised if it’s closer to 1000 runs).
Even though I’m just a member of the Joe Soap gang, this number of runs on various dyno set-ups across the UK has provided me a vast amount of knowledge around this area. I’m sure we’ve all seen the arguments about which ones do or don’t over read. How important wheel horsepower is and how inaccurate flywheel horsepower is!?
Let’s get one thing straight…. a dyno is a tool, and if used correctly, a very valuable tool.
For the pub talk fanatics out there you know which type of dyno to go to, to receive inflated figures. If that makes you feel better, bully for you….. it’s your money and your ego. Personally, I place more emphasis on accuracy and repeatability.
Remember... there are lies, damn lies and dynos!
I could tell you heaps of ways that I could alter the way a car was run on a dyno, that would influence the figures obtained. Be rest assured that this is all about being “real” from my perspective. I have nothing to gain from presenting inflated figures, and it’s certainly not something I suspect you want to see.
If you are not already aware, power figures on Rolling Roads are normally part measured and part calculated. For the purpose of this project we will be showing flywheel BHP and torque figures. The core reason behind this is that here in the UK, that is our normal method of measurement. Some people will suggest that wheel horsepower figures are the be all and end all. I totally disagree in respect of chassis dynos. Like flywheel figures, wheel horsepower figures can also be up for a “slagging”. Different chassis dynos will undoubtedly produce different wheel horsepower figures. Why? Well it’s to do with the physical makeup of the dyno, like the rollers used and how all the “gubbins” works to “measure” the power. I could then start to talk about tyre deformation and the effect this has, but I suspect that will send you to sleep.
Some others will then take the stance that it matters not what figures the dyno produces, it’s the difference of the before and after in percentage terms. With people using those % differences as a defacto way of measuring performance. You have to be open minded about this as well, as you’re assuming conditions are like for like and that the power reported is based on linear measurements on a like for like basis, with the previous run. You can not guarantee that, especially when you’re using a dyno setup that you already know provides inaccurate data.
It makes absolute sense to start off with a dyno that you feel provides accuracy from the get go. It makes no sense to start off with a dyno that you already know provides inflated figures. This is assuming you want a level of accuracy in respect of figures attained….. although there are other key (and more important) reasons why a dyno provides a worthy advantage to tuning overall. This is something that will be explained further at appropriate points in this project.
Performance measurement and tuning aids - Which type of chassis dyno?
OK…. so I want to use a dyno that provides accurate (within context) flywheel figures and repeatable results. But what about the known issue of Haldex transmission and dynos?
The A45 AMG uses a Haldex system to manage traction (torque balance) between the front and rear axles. Predominantly the system is front wheel, but has the capability to shift torque to the rear axle, when it detects slip at the front. So why is this a potential problem?
Since the Haldex system can switch to 4WD, you need to use a 4WD dyno (don’t even think about using a 2WD one!). However, many 4WD dynos have locked front and rear rollers (resistance wise), which for a permanent 4WD system (like on a Subaru) that’s all fine. For a Haldex equipped car….. that’s potentially very bad. In basic terms, running a Haldex car on a non-Haldex compatible dyno can (and has) result in damaged transmission. You need to use a dyno that is able to adjust resistance as required, between front and rear.
So let’s assume we have that situation covered with the dyno choice made.
The “cell” in which the dyno is located is also very important if you want to maintain accuracy and repeatable results.
Airflow is paramount in achieving both accuracy and a level of safety of your vehicle during dyno use. A dyno is a VERY harsh environment for your car, so you need to ensure that the best environment within the cell is provided. Decent airflow not only helps with replicating (as best as you can) road conditions, but also ensures appropriate airflow assists cooling. A properly constructed dyno “cell” will support these requirements.
There are so many so called “cells” that are effectively in part of the workshop. You’ve seen them. Big open spaces and very high ceilings. Trying to control airflow and pressure in a large space is going to be extremely difficult, if nigh on impossible with the majority of fan and exhaust systems tuners use. The smaller the “space” (cell), the better the environment can be stabilized and controlled, with appropriate fan and exhaust systems shifting huge amounts of air in and out.
So taking all of this into consideration, and based upon my previous experience of using this type of dyno (to appreciate it’s known accuracy), I’ll be using the Litchfield dyno cell equipped with the latest MAHA MSR dyno.
An added benefit of the MAHA is that it measures coast down (transmission drag) to derive a flywheel BHP figure (wheel figure + coast down). On a chassis dyno this is the only way to accurately measure transmission losses. Forget the “fixed %” that is used by so many…. drivetrain losses are not linear. Just think about heat build up (friction/drag) in your drivetrain, which builds as torque is created. The higher the temps, the more friction and greater the losses.
Oh and by the way….. Mercedes-Benz do not only use this model of dyno, but they also own quite a large number of them. If it’s good enough for them, it’s good enough for me.
AMG Test Mode for Dyno Use
Did you know that your A45 has a mode that should be used when running your car on a dyno? Well the gents at AMG decided to add a mode that disables all of the braking and traction aids (yes, that includes ABS). This is especially useful for completing runs on a dyno (I’m referring to the traction aids here), to ensure that nothing interferes.
I wonder what the car would be like on track in this mode.. Mmmmmm. Although I wouldn’t recommend this.
If you want to find out how to gain access to this mode, there is a good YT video explaining it.
Performance measurement and tuning aids - Racelogic VBOX
We know (well…. I hope we do!) it’s not all about dyno figures, and whilst I’ll be explaining how you should dissect a dyno graph to gain the important information (and that’s NOT going to be about peak figures in isolation), we really need to gauge performance on the “black stuff” surely. Part of this will be completed via road driving feedback, but that can be subjective to a degree. What we really need is another “measure” to compliment ALL the information that is being gathered.
Performance monitoring as regards to recording 0-60, 0-100 & 1/4m times was historically a bit hit and miss as far as the high street consumer has been concerned. Whilst a number of solutions have existed that are very accurate, the costs involved with these solutions had always been out of reach, except for those that require such equipment for official testing and have the budgets to substantiate such equipment.
With the advancements of GPS and the keen pricing of such equipment to the general consumer sector, a new solution appeared on the market a few years ago, that now makes this kind of performance testing, both extremely cost effective and accurate.
RaceLogic have constructed an all-in-one solution that combines a single unit that not only houses all the sensors, GPS receivers and built in screen, but it also gives the ability to log results which can be stored on a memory card and later read and analysed using some very powerful software supplied. All you need is a *** lighter socket (for power) and off you go…… sounds too simple to actually be true and accurate doesn’t it….. well let me assure you it is certainly both simple to use and very accurate. I’ve personally been using these devices for years, attaining “figures” and times which have been referenced against specialist and very expensive timing equipment.
My weapon of choice is the Racelogic Drift Box.
Firstly don’t let the name Drift Box put you off….. this little box of tricks is far more than a box that shows you drift angles!
For the purpose of this project and testing, I suspect we will be concentrating on the uses of the Performance Meter, Lap Timer and Data Logger.
Performance Meter
With the DriftBox it is very easy to measure acceleration times, braking distances, quarter miles times and much more. There are a number of configurable screens that show specific test results such as 0-60, 0-100, 0-100-0, 1/2 miles and ¼ mile etc.
DriftBox is based on the Racelogic VBOX, which is used by the majority of car manufacturers, tyre manufacturers and car magazines around the world to assess performance.
Because it is very easy to edit the test ranges, DriftBox is a very powerful tool for use in many different kinds of vehicle testing.
Lap Timer
Displaying your lap times as you drive around a circuit is simple with DriftBox. You can display your current, last and best lap times, and also display split times for up to six specified split points around the lap.
Through the DriftBox forum you are able to download circuit overlays from around the world, compare lap times, and share lap overlay data with other users.
Data Logger
Every item of data that the DriftBox displays (and loads more besides) is logged and can be recorded on a SD card. This can be read in to a PC at a later date to analyse. The piece of software that comes with the DriftBox to enable this function is very powerful indeed, giving you many different tabular and graphing facilities to display and compare the information captured. The software will even enable you to "play back" captured data sets on screen.
How accurate is it?
Amazingly accurate!!!!!
The lap timing mode proved (based on my testing) to be within .1 seconds accuracy of official track timing equipment.
The performance meter proved (based on my testing) to be within .1 seconds accuracy of several FIA approved drag strips for the 1/4m.
Right…. that’s enough “rice” for the entree.
You best visit the toilet for a bowel movement and make some space for the main course (some fitment and testing of tuning products), which will be up for “tasting” shortly!
See you in a couple of days.
Preamble
First off I would like to underline a key point. I’m not suggesting at the moment that I’m going to find out anything new or revolutionary. A lot of the initial steps I’ll be taking will undoubtedly be exactly the same as others have done before me. But I need to do it “one step at a time”, because that’s the way you learn using a pragmatic approach.
The difference with this project (I suspect) will be to go into as much detail as possible, within the context of what has been or planned to be done.
If you’re looking for “just” power graphs and peak figure talk….. whilst you’ll find that information here, this is really not what my project thread will be about - there is a lot more to modifications than just using these two elements as reference.
If I have one “mission” in life, that “mission” is to keep highlighting that on their own, peak figures mean diddly squat. If you just skim read this project, focussing on peak values and comparing those with other peak values (from others achievements), you are in my opinion, missing valuable context. Peak figures do not make for a quick car, and they certainly don’t tell you what you really need to appreciate. Peak figures are for the pub - and the next round won’t be on me!
As one community member said in comment to the introduction post, “That's a lot of rice to consume right there!”. That’s the way I roll. So you best get your empty plate ready, grab some salt and pepper, tuck your napkin in under your chin and prepare yourself for a mammoth “eat as much as you like” experience!!
I want to understand the detail of why and how, which will hopefully allow us all to understand how things could be improved and what is potentially looked at next in the journey.
First thing is to state that Litchfield Motors will be key company I’ll be working with at this stage.
Why choose Litchfield?
You may be thinking that Litchfield have no real presence in the MB tuning scene at present (although that does not mean they have not been developing products for the MB marque), so why would I be working with them when there are other well established MB tuners in this scene.
I’m not going to go into a full on promo speech about Litchfield. Their past creations like their Type 20, Type 25, Time Attack winning Type 25 Race Car and their recent GTR and BMW developments tell you an impressive story. Let alone the intrinsic involvement they have had with my own “Project Cars”, which have had their own “notoriety” within the Subaru community over the past 10 yrs.
What is certainly within context of this project is:
I’ve worked with Litchfield on a number of projects before (for well over 10yrs), albeit within the Subaru scene. They have proved to me without doubt, that they are absolutely committed to achieving excellence, having a vast amount of tuning and development experience…. with their key goal to always create and sell packages that make a car very quick on the road, delivering what the customer really wants - even if the customer doesn’t always know what they want. They are absolutely passionate about this.
Litchfield also understand, support and appreciate the benefits that an “open project” like this can provide…… not all tuning companies “get” this kind of approach and would rather keep things “hush hush” - I’m all about sharing as much information as I can with the community (it’s what really drives me to do this kind of project work) - Litchfield wholeheartedly support this approach.
Litchfield also have a well established technical partner network which includes Turbo Dynamics, AET Turbos, EcuTEK, COBB, Syvecs, Whiteline, Bilstein, Eibach, Miltek, Akrapovic, Forge, Alcon etc. This is a massive plus to me and this project, as these companies are some of the “big hitters” in the industry. This will only help support any proposed development in my opinion.
Last but by no means least is the expertise/facilities that Litchfield possess “in house”. They have a large workshop facility which includes a multitude of ramps, alignment rigs, engine/gearbox build rooms, engine dyno and cell, chassis dyno and cell, fabrication facilities (i.e. they can produce their own exhaust systems in-house for prototyping). Litchfields also have a vast amount of engine calibration tools and expertise, to develop “methods” and utilise those “methods” to maximise the potential that ECU mapping (which is also completed on-site by Litchfield) can present.
With a number of the projects that either Litchfield have commissioned themselves, or supported those commissioned by others, they have built a massive amount of knowledge and expertise. They don’t only develop and deliver great road car packages, but they are also able to produce packages that do the business in competition on track.
Having the opportunity to work with a company that possess these facilities, level of experience and passion, should hopefully benefit the progression of this project.
Performance measurement and tuning aids - Rolling Road Overview
Perhaps the single biggest bone of contention is how I would decide to measure/test for any increases (and of course decreases) in power, when looking at engine modifications. Several ways exist, namely use of a Rolling Road, Engine Dyno, Performance Meters and the regularly used “**** dyno” (for those that are not familiar with this, it is the term given to the “just driven my car and it feels so much quicker now…. It must be 400bhp”).
For the purpose of engine based modifications, stats will be attained by use of a Rolling Road, coupled with real driving feedback on the road.
Even though we may all agree that various rolling roads will give different readings, and the arguments that RR figures at X are incorrect and RR figures at Y are correct, is meaningless to a degree.
Although many conditions even on the same rolling road can cause changes in figures, we need something we can use to compare with accuracy and repeatability. Obviously the more conditions you can stabilise the more your figures will be representative.
Now, before I explain things further it’s probably worth me stating one thing here and now. I’m a self confessed “dyno queen”. At a guess, I suspect I have had well in excess of 500 runs on various dyno’s over the years (I wouldn’t actually be surprised if it’s closer to 1000 runs).
Even though I’m just a member of the Joe Soap gang, this number of runs on various dyno set-ups across the UK has provided me a vast amount of knowledge around this area. I’m sure we’ve all seen the arguments about which ones do or don’t over read. How important wheel horsepower is and how inaccurate flywheel horsepower is!?
Let’s get one thing straight…. a dyno is a tool, and if used correctly, a very valuable tool.
For the pub talk fanatics out there you know which type of dyno to go to, to receive inflated figures. If that makes you feel better, bully for you….. it’s your money and your ego. Personally, I place more emphasis on accuracy and repeatability.
Remember... there are lies, damn lies and dynos!
I could tell you heaps of ways that I could alter the way a car was run on a dyno, that would influence the figures obtained. Be rest assured that this is all about being “real” from my perspective. I have nothing to gain from presenting inflated figures, and it’s certainly not something I suspect you want to see.
If you are not already aware, power figures on Rolling Roads are normally part measured and part calculated. For the purpose of this project we will be showing flywheel BHP and torque figures. The core reason behind this is that here in the UK, that is our normal method of measurement. Some people will suggest that wheel horsepower figures are the be all and end all. I totally disagree in respect of chassis dynos. Like flywheel figures, wheel horsepower figures can also be up for a “slagging”. Different chassis dynos will undoubtedly produce different wheel horsepower figures. Why? Well it’s to do with the physical makeup of the dyno, like the rollers used and how all the “gubbins” works to “measure” the power. I could then start to talk about tyre deformation and the effect this has, but I suspect that will send you to sleep.
Some others will then take the stance that it matters not what figures the dyno produces, it’s the difference of the before and after in percentage terms. With people using those % differences as a defacto way of measuring performance. You have to be open minded about this as well, as you’re assuming conditions are like for like and that the power reported is based on linear measurements on a like for like basis, with the previous run. You can not guarantee that, especially when you’re using a dyno setup that you already know provides inaccurate data.
It makes absolute sense to start off with a dyno that you feel provides accuracy from the get go. It makes no sense to start off with a dyno that you already know provides inflated figures. This is assuming you want a level of accuracy in respect of figures attained….. although there are other key (and more important) reasons why a dyno provides a worthy advantage to tuning overall. This is something that will be explained further at appropriate points in this project.
Performance measurement and tuning aids - Which type of chassis dyno?
OK…. so I want to use a dyno that provides accurate (within context) flywheel figures and repeatable results. But what about the known issue of Haldex transmission and dynos?
The A45 AMG uses a Haldex system to manage traction (torque balance) between the front and rear axles. Predominantly the system is front wheel, but has the capability to shift torque to the rear axle, when it detects slip at the front. So why is this a potential problem?
Since the Haldex system can switch to 4WD, you need to use a 4WD dyno (don’t even think about using a 2WD one!). However, many 4WD dynos have locked front and rear rollers (resistance wise), which for a permanent 4WD system (like on a Subaru) that’s all fine. For a Haldex equipped car….. that’s potentially very bad. In basic terms, running a Haldex car on a non-Haldex compatible dyno can (and has) result in damaged transmission. You need to use a dyno that is able to adjust resistance as required, between front and rear.
So let’s assume we have that situation covered with the dyno choice made.
The “cell” in which the dyno is located is also very important if you want to maintain accuracy and repeatable results.
Airflow is paramount in achieving both accuracy and a level of safety of your vehicle during dyno use. A dyno is a VERY harsh environment for your car, so you need to ensure that the best environment within the cell is provided. Decent airflow not only helps with replicating (as best as you can) road conditions, but also ensures appropriate airflow assists cooling. A properly constructed dyno “cell” will support these requirements.
There are so many so called “cells” that are effectively in part of the workshop. You’ve seen them. Big open spaces and very high ceilings. Trying to control airflow and pressure in a large space is going to be extremely difficult, if nigh on impossible with the majority of fan and exhaust systems tuners use. The smaller the “space” (cell), the better the environment can be stabilized and controlled, with appropriate fan and exhaust systems shifting huge amounts of air in and out.
So taking all of this into consideration, and based upon my previous experience of using this type of dyno (to appreciate it’s known accuracy), I’ll be using the Litchfield dyno cell equipped with the latest MAHA MSR dyno.
An added benefit of the MAHA is that it measures coast down (transmission drag) to derive a flywheel BHP figure (wheel figure + coast down). On a chassis dyno this is the only way to accurately measure transmission losses. Forget the “fixed %” that is used by so many…. drivetrain losses are not linear. Just think about heat build up (friction/drag) in your drivetrain, which builds as torque is created. The higher the temps, the more friction and greater the losses.
Oh and by the way….. Mercedes-Benz do not only use this model of dyno, but they also own quite a large number of them. If it’s good enough for them, it’s good enough for me.
AMG Test Mode for Dyno Use
Did you know that your A45 has a mode that should be used when running your car on a dyno? Well the gents at AMG decided to add a mode that disables all of the braking and traction aids (yes, that includes ABS). This is especially useful for completing runs on a dyno (I’m referring to the traction aids here), to ensure that nothing interferes.
I wonder what the car would be like on track in this mode.. Mmmmmm. Although I wouldn’t recommend this.
If you want to find out how to gain access to this mode, there is a good YT video explaining it.
Performance measurement and tuning aids - Racelogic VBOX
We know (well…. I hope we do!) it’s not all about dyno figures, and whilst I’ll be explaining how you should dissect a dyno graph to gain the important information (and that’s NOT going to be about peak figures in isolation), we really need to gauge performance on the “black stuff” surely. Part of this will be completed via road driving feedback, but that can be subjective to a degree. What we really need is another “measure” to compliment ALL the information that is being gathered.
Performance monitoring as regards to recording 0-60, 0-100 & 1/4m times was historically a bit hit and miss as far as the high street consumer has been concerned. Whilst a number of solutions have existed that are very accurate, the costs involved with these solutions had always been out of reach, except for those that require such equipment for official testing and have the budgets to substantiate such equipment.
With the advancements of GPS and the keen pricing of such equipment to the general consumer sector, a new solution appeared on the market a few years ago, that now makes this kind of performance testing, both extremely cost effective and accurate.
RaceLogic have constructed an all-in-one solution that combines a single unit that not only houses all the sensors, GPS receivers and built in screen, but it also gives the ability to log results which can be stored on a memory card and later read and analysed using some very powerful software supplied. All you need is a *** lighter socket (for power) and off you go…… sounds too simple to actually be true and accurate doesn’t it….. well let me assure you it is certainly both simple to use and very accurate. I’ve personally been using these devices for years, attaining “figures” and times which have been referenced against specialist and very expensive timing equipment.
My weapon of choice is the Racelogic Drift Box.
Firstly don’t let the name Drift Box put you off….. this little box of tricks is far more than a box that shows you drift angles!
For the purpose of this project and testing, I suspect we will be concentrating on the uses of the Performance Meter, Lap Timer and Data Logger.
Performance Meter
With the DriftBox it is very easy to measure acceleration times, braking distances, quarter miles times and much more. There are a number of configurable screens that show specific test results such as 0-60, 0-100, 0-100-0, 1/2 miles and ¼ mile etc.
DriftBox is based on the Racelogic VBOX, which is used by the majority of car manufacturers, tyre manufacturers and car magazines around the world to assess performance.
Because it is very easy to edit the test ranges, DriftBox is a very powerful tool for use in many different kinds of vehicle testing.
Lap Timer
Displaying your lap times as you drive around a circuit is simple with DriftBox. You can display your current, last and best lap times, and also display split times for up to six specified split points around the lap.
Through the DriftBox forum you are able to download circuit overlays from around the world, compare lap times, and share lap overlay data with other users.
Data Logger
Every item of data that the DriftBox displays (and loads more besides) is logged and can be recorded on a SD card. This can be read in to a PC at a later date to analyse. The piece of software that comes with the DriftBox to enable this function is very powerful indeed, giving you many different tabular and graphing facilities to display and compare the information captured. The software will even enable you to "play back" captured data sets on screen.
How accurate is it?
Amazingly accurate!!!!!
The lap timing mode proved (based on my testing) to be within .1 seconds accuracy of official track timing equipment.
The performance meter proved (based on my testing) to be within .1 seconds accuracy of several FIA approved drag strips for the 1/4m.
Right…. that’s enough “rice” for the entree.
You best visit the toilet for a bowel movement and make some space for the main course (some fitment and testing of tuning products), which will be up for “tasting” shortly!
See you in a couple of days.
22 February 2015, 11:19 AM
#38
Scooby Regular
Thread Starter
You guys have been used to my approach for years, so I can only apologise for that level of upfront "intro" information.
The next update will provide the real "guts" of the initial investigatory work. IMO the torque out of this current stage of tune is pretty "epic" for a 2ltr.
The next update will provide the real "guts" of the initial investigatory work. IMO the torque out of this current stage of tune is pretty "epic" for a 2ltr.
27 February 2015, 08:04 AM
#44
Scooby Regular
Thread Starter
Like for like power levels, it's all over the Hawkeye like a rash - which you would expect tbh. This is 10yrs+ newer product.
I should have all the data documented for release, over this weekend.
Christ, this has taken me ages lol - which hasn't been helped by me getting sucked into "Tuner Wars" on the MB forums.
There are some proper underhand MB tuners (well one) out there, who will do anything to discredit others and their work. It reminded me of the SN scene 10yrs ago! The can of "whup ***" is about to be opened shortly. 
I should have all the data documented for release, over this weekend.
Christ, this has taken me ages lol - which hasn't been helped by me getting sucked into "Tuner Wars" on the MB forums.
There are some proper underhand MB tuners (well one) out there, who will do anything to discredit others and their work. It reminded me of the SN scene 10yrs ago!
The can of "whup ***" is about to be opened shortly.
27 February 2015, 08:26 AM
#45
Like for like power levels, it's all over the Hawkeye like a rash - which you would expect tbh. This is 10yrs+ newer product.
I should have all the data documented for release, over this weekend.
Christ, this has taken me ages lol - which hasn't been helped by me getting sucked into "Tuner Wars" on the MB forums.
There are some proper underhand MB tuners (well one) out there, who will do anything to discredit others and their work. It reminded me of the SN scene 10yrs ago! The can of "whup ***" is about to be opened shortly.
I should have all the data documented for release, over this weekend.
Christ, this has taken me ages lol - which hasn't been helped by me getting sucked into "Tuner Wars" on the MB forums.
There are some proper underhand MB tuners (well one) out there, who will do anything to discredit others and their work. It reminded me of the SN scene 10yrs ago!
The can of "whup ***" is about to be opened shortly. You'll have your detractors on MB forums as well as here willing you to fail. Unbeknownst to them that that is the very thing which spurs you on. Do you have a link to the MB forum thread.
28 February 2015, 06:49 AM
#46
Scooby Regular
Thread Starter
TBH Maz the project threads have been "clean". It's stuff that has been going on in other threads and Face Book.
I'll just let my "real world" VBOX results do the talking.
This one is already making a stir:
Anyway.... I'm off to see Litcho today, as I need some more data for the update (I've got graphs, tables and logs coming out of my ears at the moment).
Expect a full update on everything by the end of this weekend.
Here's one of the threads you may find interesting though: http://www.aclassclub.co.uk/forum/ri...topic5442.html
I'll just let my "real world" VBOX results do the talking.
This one is already making a stir:
Anyway.... I'm off to see Litcho today, as I need some more data for the update (I've got graphs, tables and logs coming out of my ears at the moment).
Expect a full update on everything by the end of this weekend.
Here's one of the threads you may find interesting though: http://www.aclassclub.co.uk/forum/ri...topic5442.html
28 February 2015, 03:58 PM
#47
Scooby Regular
Thread Starter
Apologies for splitting this update...... it's humongous even by my standards!!
Engine Stage 1 - Tuning Box
So here we are: The engine. Stage 1. Tuning Box.
Let’s get to it…..
Apologies to those of you who understand the theory side of tuning, or those that are simply not interested. Something I like to do is provide some background physics explanation and/or theories, when I explain new elements that are being investigated and/or tested. Many people find this interesting and I feel it adds appropriate context to the what and why questions.
The old skool way of anything relating to “Stage 1” used to be exhaust, air filter and a carburettor rejetting and/or ignition timing alterations. Whilst methods may have changed since the “old days”, the principals remain the same.
In respect of the internal combustion engine: more air in (and more exhaust gas out), more fuel in, more ignition, bigger bang and what do we have……. more POWER!!
Luckily with modern set-ups, (read: ECU’s) and of course forced induction (turbo charging), the results can be quite dramatic, with relatively little effort.
Talking of turbo charging, whilst I suspect we know what this term relates to, do we all actually know how it works?
Simply put:
- air is effectively sucked in through the air filter; through the compressor side of the turbo (which, as the name suggests compresses the air to make it more dense by volume);
- through a cooling unit to increase/retain density, into the combustion chamber of each cylinder;
- this air is nice and dense (compared to an engine that is not turbocharged), so when you add fuel (proportionally) and introduce a spark you get a much bigger bang;
- on the downward stroke of the piston the exhaust gas passes through the exhaust manifold/headers (via the exhaust valves opening), through the turbo (exhaust side), which drives the compressor (compressor and exhaust on the turbo core work together - suck and blow air) and the cycle starts again.
Sounds quite complicated to explain but the physics are pretty simple.
Basic engine “tuning” nowadays (more so for turbocharged vehicles) normally relates to an ECU (Engine Control Unit) “remap”. Which crudely put, is done by changing values within the ECU “map”, which tells your engine what to do in relation to fuel, air and ignition.
Same as “old days”, just using different methods to control it all.
For the majority of us we don’t really care what this side entails. As long as we get the expected results, who cares what parameters have to be changed and for what reason…… but equally there are a number of us who are interested.
Mapping needs to be undertaken by a professional that really knows their stuff. Many people claim they are experts, but in my experience, this does not always relate to a good job. Whether that relates to a fast car (or not), or probably more importantly, one that doesn’t grenade itself due to a bad map. In my opinion one of the biggest and most key decisions you’ll ever make when tuning a car, is who maps it and should you require this, who builds you an engine. NEVER take these decisions lightly. Do your research guys (as I’m sure some of you are already too well aware of).
Tuning Box
Whilst I would have loved to get straight into ECU remapping as the first “venture”, I needed to look at these tuning boxes first, which are quite the “in thing” with the A45 at the moment.
Nasty way of tuning or actually a method that can work? I used to always think the former if I’m being honest.
Coming from the Subaru scene (my previous life) you’d never dream of using a tuning box. In fact I never liked the idea of using these devices even with my daily diesel hack. However, I’m always open to some testing and finding stuff out.
So what does a tuning box actually do (yeah, yeah - it tunes!!!)...
Whilst we’ve established the basics of air, fuel and spark make power, and we’ve also stated that modern engines control all of this via the ECU. Where does a tuning box fit in all of this then?
Most tuning boxes effectively sit between certain engine sensors, reading data going to or coming from a sensor, from or to the ECU. A tuning box can basically “alter” data between what is read in and what is sent out of it.
The most crude of tuning boxes will simply use a form of linear resistance bridged either over one sensor or between two. These types of tuning boxes would be best avoided in my opinion.
The most advanced ones have heavily populated data tables on them, which cross reference many things to provide safer control, across multiple sensors, and even allow you to make incremental changes to the overall settings of the box. This provides an element of flexibility for differing conditions and environments.
Even after doing my research on tuning boxes I still felt a bit uneasy, as “altering” data between the sensors and ECU never really sat well with me, as I was always concerned about the safety elements, that effectively the ECU would not be in total control.
This is where modern ECU’s appear to help the cause.
Modern ECU’s can have a lot of self learning and to a degree, on the fly mapping adjustment capabilities. Many ECU’s are now able to adjust fueling and ignition (within certain boundaries) based upon readings from a number of the engine sensors. So even if a tuning box requests more boost, the ECU detects that a fuel mixture is running lean and will add more fuel to compensate (again, being very simplistic). Assuming the tuning box works in conjunction with the ECU capabilities and engine, you could have quite a nifty setup available for a Stage 1 tune.
The single biggest advantage of a tuning box, is because it sits between your ECU and sensors, it can be easily removed and (in most cases) undetectable - read: warranty friendly.
I would suggest the biggest downside (let’s assume the tune levels and setup is safe) is that a “proper” remap (which may also bring issues around warranty) of the ECU tables may provide better gains. Not always in peak figures for Stage 1, but a custom map of your car will probably net driveability gains. But we’ll test that theory at a later stage.
So before fitting the Litchfield tuning box I needed to gain a baseline with the A45 in standard guise.
Just for clarity we will conduct three runs for each test. The first one to ensure the engine, ancillaries and transmission are up to effective temperature, and the final two to gauge consistency of figures.
The MAHA dyno simulates quite a lot of load, and the runs can be longer than on some other dynos. As long as the dyno cell has proper/effective airflow, this won’t be an issue and it helps to ensure that appropriate load is being seen by the engine and ECU for each run (as you would see on the road).
Something else I’ll be making use of, to ensure that I can gauge an element of satisfaction around what the ECU is seeing and how the engine is reacting, is to monitor detonation/knock. This is very important when you’re tuning a car, to appreciate whether or not you’re getting pre-ignition. This can be caused by all manner of things, and is ultimately bad news for your engine (damage to pistons, rings and crank bearings etc). I’m sure you’ve all heard of tuned engines that have melted a piston....... knock is your enemy.
The ECU will have it’s own knock strategy (many modern ECU’s are so powerful nowadays), and be surly recording any knock events (via a knock sensor located on the engine block) in it’s logs. It will use this information to “learn” (within certain boundaries), adapting ignition (by retarding) etc to reduce the occurrence of any knock event, once an event has been “seen”. Once we get into the ECU side of things we should be able to log this more effectively. For the time being we’ll be using DET CANS whilst testing work is being done on the dyno and road, to ensure we can “listen” for any knock events that happen. This is in part, to make sure any level of tune is “safe”. In laymans terms, DET CANS consist of a microphone and a set of head phones. The noise of DET happening can be distinguished through the headphones, to a person who has a trained ear.
Dyno Corrections Used
I want to get this out of the way, to provide ABSOLUTE clarity to the dyno results we will see throughout this project.
Nearly every dyno has a correction facility, which based on whatever correction factor is being applied, will use data from the environment (barometric pressure, inlet temps, ambient temps etc) in conjunction with a calculation, to normalise the power readings. This is to ensure (any dyno accuracy of readings in general to one side) that it does not matter (to a degree) whether you dyno your car on a hot day or a cold day, your figures will be comparative. These correction factors are a leveller to normalise figures regardless of environment atmospheric conditions. Basically, if any one says to you that their dyno figure was low, because it was “hot outside”..... they are more likely giving an excuse for something that is not actually a reason.
I would suggest that you only use a dyno that has corrections applied, for any reasonable power output figure. You’ll see why below.
The large majority of data and dyno set-ups in the EU will use the DIN correction factor. However, the latest correction factor that is being adopted across the EU now (and certainly by the manufacturers) is EWG. The short and tall of it, is EWG will generally provide LOWER figures than DIN.
Based on my dyno testing (of the baseline standard figures) the differences were:
Uncorrected power: 390.1 BHP
Corrected to DIN: 376.5 BHP
Corrected to EWG: 363.6 BHP This is extremely close to manufacturers figures.
You can see there is a difference between all of them. Make sure your dyno graph has a correction factor for starters, and then ensure any other graph you’re comparing with, is using the same factor. Don’t forget the differences can sway both ways as well.
If you compound correction factors with, “optimistic” dynos, you’ll now start to understand why there is some major disparity with dyno numbers in the wild. Certainly with some of the figures being touted around the forums.
Just be open minded about all of this….. AND DON’T CONCENTRATE ON DYNO NUMBERS in isolation!
Since nearly all the comparable data in the community for the A45 has been measured by using DIN, that will be the correction factor I’ll be using for the time being (it will be clearly marked as such on each graph).
TEST 1 - Baseline Figure
Summary of Spec
Standard MY14 A45 AMG
Fuel - VPower Nitro (99 oct)
TEST 1 figure achieved was 376.5bhp & 334.8lbft @ the flywheel
TEST 1 - Baseline Figure - Comments
Well we already appreciate how quick this car is, even in standard form on the black stuff. But in reality this is due to a number of things. The area under the curve, the gearbox and Haldex system - as a complete package it pretty much rocks, but what does the “pretty” graph tell us about the power delivery.
The area under the curve is always more relevant than the peak figures.
I can normally look at an entire power graph and make a decent judgement as to the potential of the power delivery and flexibility on the road, taking into account the power band and torque available. Make no mistake, it’s the torque that gets you to where you want to go…. quicker.
Since the MAHA RR is able to appropriately load the engine up, you can deduce how the turbo comes on song. You can see here that you’re achieving near (over 320lbft) peak torque at around 2800rpm, which in 4th gear is really very good on a 2ltr. Suffice to say, due to loading, you will see peak torque coming in slightly earlier the higher the gear. So 5th would see this 2800rpm drop slightly….. this is all normal (3rd gear would be slightly later and so on).
Low rpm’s for torque makes for more pace from lower revs, however by looking at this torque curve you see the A45 holds this torque all the way through to 6k rpm. Again, for a 2ltr this is pretty awesome. This is why the mid-range feels really strong on the A45 and explains why the engine just keeps pulling to the redline. When you combine a wide torque band, with an early onset of torque, you end up with a very agile package.
When we also see how much more power/torque this turbo can provide further on, it makes the overall set-up even more amazing.
So what else can we find out?
Another advantage of the MAHA RR is that we can also capture and overlay other data, that is gathered at the time of the dyno run. For these stage of tests against Stage 1, we’ll access additional data direct from the ECU (via the ODB port) and feed these into the dyno hardware. Later on in future stages I’ll look at capturing all manner of data via software accessing the ECU directly (which will enable more information to be captured).
TEST 1 Boost Plot
The problem with logging via OBD is that the logging sample rate can be quite slow (hence why the plot is very angular). Also with boost, OBD is capped to around 1.55bar, so the plot levels out at this (the scale is in absolute, so you need to take a whole number off to get the boost pressure - i.e. 2.5bar absolute is 1.5bar boost). The graph looks like max boost is 1.55bar, which it won’t be in reality.
I’ll get these graphs refreshed with proper boost plotting, so we can see what the max boost is. I don’t even know what this is, as I wasn’t able to log it…. we’ll find out don’t worry.
Putting the above slight issue to one side…..
The first thing that “shocked” me when I saw the standard run boost graph, was the boost profile. I’m used to a car hitting peak boost just prior to peak torque and then trying to hold that boost through the mid-range, and then falling off towards the latter part of the rev range.
Not with the A45 it doesn't! However, once you start thinking about it (taking the torque graph into account), it all makes sense. The boost is profiled like this to keep the torque curve nice and flat, which aids driveability and potentially enables the top end power to be retained at a higher RPM. I also think this is an emissions “thing” as well…. we’ll see more on that when we look at the fuelling side of things.
The harder and earlier you “work” a turbo, the earlier (within the rev range) it can start to run past it’s efficiency, inturn pumping hot air. Taking the approach that AMG have, means you end up with a really good powerband…. ergo a quicker car on the road.
There was me originally thinking (as we’re told that this turbo is operating at 1.8bar as OEM set-up) that this turbo must be some monster technology to make 1.8bar at just over 2k and holding through the mid-range. Not at all….. AMG have just used a different approach to give the best powerband, and ultimately a quicker car. Nothing groundbreaking, but a really good approach in this instance.
As you can see by the boost plot, the mid-range is only running around 1.35bar. We’re seeing 1bar at a little over 2200rpm. In 4th gear on a dyno that is pretty awesome.
TEST 1 Ignition Plot
So here we have the standard ignition map. On it’s own it’s fairly irrelevant, but as we look at the differences of the before and after (tuning box), we’ll have something else to “inspect”.
The only thing worth saying is that you’ll be able to see how the ignition is ramped up as we gain revs on the standard set-up. Currently peak ignition is showing advance of 12degs @ 6k rpm.
TEST 1 Lambda Plot
Since this graph is showing what the ECU is seeing via OBD, this is from the lambda prior to the CAT. On new cars like the A45, this specific lambda sensor is pseudo “wideband”. This is much more accurate and quicker lambda sensor, than what we used to see in cars a few years back. I’ll tell you why this is important once we talk about the tuning box testing.
Like when I saw the boost curve, I was also quite shocked when I saw the lambda plot. The A45 likes to run very lean by the looks of it!
You can see by the graph that the fueling starts off rich as you come on boost, and then leans right out. Then gradually the fueling starts to richen back up again, until at peak power it’s about the level that you would normally aim for on a tune.
The leaner the engine runs, the hotter it runs and the cleaner the burn cycle….. which ultimately means less emissions. If you wondered why the A45 can achieve so good emissions, this will be one of the reasons. Obviously the engine is designed to run this hot, but I wouldn’t feel comfortable running a car this lean as a strategy moving forward (when we look at future mods for more serious power).
For me, this was another set of interesting data logs, which now start to explain quite a few things about the A45, but also gives us areas to “play with” in the future.
TEST 1 Road
There is no point in having a “Road Test” overview…… you all know how these cars drive in standard form. However, to date I have no OEM state of tune VBOX logs. I can capture this information if it appears prudent to do so, but I think there is enough information out in the wild, that we appreciate the OEM numbers (like 0-60 and 0-100mph etc).
When all’s said and done, the key thing we have here is a baseline to reference against, for any engine mods we decide to do hereon.
Full results from the Litchfield Tuning Box will be up within 24hrs!
Engine Stage 1 - Tuning Box
So here we are: The engine. Stage 1. Tuning Box.
Let’s get to it…..
Apologies to those of you who understand the theory side of tuning, or those that are simply not interested. Something I like to do is provide some background physics explanation and/or theories, when I explain new elements that are being investigated and/or tested. Many people find this interesting and I feel it adds appropriate context to the what and why questions.
The old skool way of anything relating to “Stage 1” used to be exhaust, air filter and a carburettor rejetting and/or ignition timing alterations. Whilst methods may have changed since the “old days”, the principals remain the same.
In respect of the internal combustion engine: more air in (and more exhaust gas out), more fuel in, more ignition, bigger bang and what do we have……. more POWER!!
Luckily with modern set-ups, (read: ECU’s) and of course forced induction (turbo charging), the results can be quite dramatic, with relatively little effort.
Talking of turbo charging, whilst I suspect we know what this term relates to, do we all actually know how it works?
Simply put:
- air is effectively sucked in through the air filter; through the compressor side of the turbo (which, as the name suggests compresses the air to make it more dense by volume);
- through a cooling unit to increase/retain density, into the combustion chamber of each cylinder;
- this air is nice and dense (compared to an engine that is not turbocharged), so when you add fuel (proportionally) and introduce a spark you get a much bigger bang;
- on the downward stroke of the piston the exhaust gas passes through the exhaust manifold/headers (via the exhaust valves opening), through the turbo (exhaust side), which drives the compressor (compressor and exhaust on the turbo core work together - suck and blow air) and the cycle starts again.
Sounds quite complicated to explain but the physics are pretty simple.
Basic engine “tuning” nowadays (more so for turbocharged vehicles) normally relates to an ECU (Engine Control Unit) “remap”. Which crudely put, is done by changing values within the ECU “map”, which tells your engine what to do in relation to fuel, air and ignition.
Same as “old days”, just using different methods to control it all.
For the majority of us we don’t really care what this side entails. As long as we get the expected results, who cares what parameters have to be changed and for what reason…… but equally there are a number of us who are interested.
Mapping needs to be undertaken by a professional that really knows their stuff. Many people claim they are experts, but in my experience, this does not always relate to a good job. Whether that relates to a fast car (or not), or probably more importantly, one that doesn’t grenade itself due to a bad map. In my opinion one of the biggest and most key decisions you’ll ever make when tuning a car, is who maps it and should you require this, who builds you an engine. NEVER take these decisions lightly. Do your research guys (as I’m sure some of you are already too well aware of).
Tuning Box
Whilst I would have loved to get straight into ECU remapping as the first “venture”, I needed to look at these tuning boxes first, which are quite the “in thing” with the A45 at the moment.
Nasty way of tuning or actually a method that can work? I used to always think the former if I’m being honest.
Coming from the Subaru scene (my previous life) you’d never dream of using a tuning box. In fact I never liked the idea of using these devices even with my daily diesel hack. However, I’m always open to some testing and finding stuff out.
So what does a tuning box actually do (yeah, yeah - it tunes!!!)...
Whilst we’ve established the basics of air, fuel and spark make power, and we’ve also stated that modern engines control all of this via the ECU. Where does a tuning box fit in all of this then?
Most tuning boxes effectively sit between certain engine sensors, reading data going to or coming from a sensor, from or to the ECU. A tuning box can basically “alter” data between what is read in and what is sent out of it.
The most crude of tuning boxes will simply use a form of linear resistance bridged either over one sensor or between two. These types of tuning boxes would be best avoided in my opinion.
The most advanced ones have heavily populated data tables on them, which cross reference many things to provide safer control, across multiple sensors, and even allow you to make incremental changes to the overall settings of the box. This provides an element of flexibility for differing conditions and environments.
Even after doing my research on tuning boxes I still felt a bit uneasy, as “altering” data between the sensors and ECU never really sat well with me, as I was always concerned about the safety elements, that effectively the ECU would not be in total control.
This is where modern ECU’s appear to help the cause.
Modern ECU’s can have a lot of self learning and to a degree, on the fly mapping adjustment capabilities. Many ECU’s are now able to adjust fueling and ignition (within certain boundaries) based upon readings from a number of the engine sensors. So even if a tuning box requests more boost, the ECU detects that a fuel mixture is running lean and will add more fuel to compensate (again, being very simplistic). Assuming the tuning box works in conjunction with the ECU capabilities and engine, you could have quite a nifty setup available for a Stage 1 tune.
The single biggest advantage of a tuning box, is because it sits between your ECU and sensors, it can be easily removed and (in most cases) undetectable - read: warranty friendly.
I would suggest the biggest downside (let’s assume the tune levels and setup is safe) is that a “proper” remap (which may also bring issues around warranty) of the ECU tables may provide better gains. Not always in peak figures for Stage 1, but a custom map of your car will probably net driveability gains. But we’ll test that theory at a later stage.
So before fitting the Litchfield tuning box I needed to gain a baseline with the A45 in standard guise.
Just for clarity we will conduct three runs for each test. The first one to ensure the engine, ancillaries and transmission are up to effective temperature, and the final two to gauge consistency of figures.
The MAHA dyno simulates quite a lot of load, and the runs can be longer than on some other dynos. As long as the dyno cell has proper/effective airflow, this won’t be an issue and it helps to ensure that appropriate load is being seen by the engine and ECU for each run (as you would see on the road).
Something else I’ll be making use of, to ensure that I can gauge an element of satisfaction around what the ECU is seeing and how the engine is reacting, is to monitor detonation/knock. This is very important when you’re tuning a car, to appreciate whether or not you’re getting pre-ignition. This can be caused by all manner of things, and is ultimately bad news for your engine (damage to pistons, rings and crank bearings etc). I’m sure you’ve all heard of tuned engines that have melted a piston....... knock is your enemy.
The ECU will have it’s own knock strategy (many modern ECU’s are so powerful nowadays), and be surly recording any knock events (via a knock sensor located on the engine block) in it’s logs. It will use this information to “learn” (within certain boundaries), adapting ignition (by retarding) etc to reduce the occurrence of any knock event, once an event has been “seen”. Once we get into the ECU side of things we should be able to log this more effectively. For the time being we’ll be using DET CANS whilst testing work is being done on the dyno and road, to ensure we can “listen” for any knock events that happen. This is in part, to make sure any level of tune is “safe”. In laymans terms, DET CANS consist of a microphone and a set of head phones. The noise of DET happening can be distinguished through the headphones, to a person who has a trained ear.
Dyno Corrections Used
I want to get this out of the way, to provide ABSOLUTE clarity to the dyno results we will see throughout this project.
Nearly every dyno has a correction facility, which based on whatever correction factor is being applied, will use data from the environment (barometric pressure, inlet temps, ambient temps etc) in conjunction with a calculation, to normalise the power readings. This is to ensure (any dyno accuracy of readings in general to one side) that it does not matter (to a degree) whether you dyno your car on a hot day or a cold day, your figures will be comparative. These correction factors are a leveller to normalise figures regardless of environment atmospheric conditions. Basically, if any one says to you that their dyno figure was low, because it was “hot outside”..... they are more likely giving an excuse for something that is not actually a reason.
I would suggest that you only use a dyno that has corrections applied, for any reasonable power output figure. You’ll see why below.
The large majority of data and dyno set-ups in the EU will use the DIN correction factor. However, the latest correction factor that is being adopted across the EU now (and certainly by the manufacturers) is EWG. The short and tall of it, is EWG will generally provide LOWER figures than DIN.
Based on my dyno testing (of the baseline standard figures) the differences were:
Uncorrected power: 390.1 BHP
Corrected to DIN: 376.5 BHP
Corrected to EWG: 363.6 BHP This is extremely close to manufacturers figures.
You can see there is a difference between all of them. Make sure your dyno graph has a correction factor for starters, and then ensure any other graph you’re comparing with, is using the same factor. Don’t forget the differences can sway both ways as well.
If you compound correction factors with, “optimistic” dynos, you’ll now start to understand why there is some major disparity with dyno numbers in the wild. Certainly with some of the figures being touted around the forums.
Just be open minded about all of this….. AND DON’T CONCENTRATE ON DYNO NUMBERS in isolation!
Since nearly all the comparable data in the community for the A45 has been measured by using DIN, that will be the correction factor I’ll be using for the time being (it will be clearly marked as such on each graph).
TEST 1 - Baseline Figure
Summary of Spec
Standard MY14 A45 AMG
Fuel - VPower Nitro (99 oct)
TEST 1 figure achieved was 376.5bhp & 334.8lbft @ the flywheel
TEST 1 - Baseline Figure - Comments
Well we already appreciate how quick this car is, even in standard form on the black stuff. But in reality this is due to a number of things. The area under the curve, the gearbox and Haldex system - as a complete package it pretty much rocks, but what does the “pretty” graph tell us about the power delivery.
The area under the curve is always more relevant than the peak figures.
I can normally look at an entire power graph and make a decent judgement as to the potential of the power delivery and flexibility on the road, taking into account the power band and torque available. Make no mistake, it’s the torque that gets you to where you want to go…. quicker.
Since the MAHA RR is able to appropriately load the engine up, you can deduce how the turbo comes on song. You can see here that you’re achieving near (over 320lbft) peak torque at around 2800rpm, which in 4th gear is really very good on a 2ltr. Suffice to say, due to loading, you will see peak torque coming in slightly earlier the higher the gear. So 5th would see this 2800rpm drop slightly….. this is all normal (3rd gear would be slightly later and so on).
Low rpm’s for torque makes for more pace from lower revs, however by looking at this torque curve you see the A45 holds this torque all the way through to 6k rpm. Again, for a 2ltr this is pretty awesome. This is why the mid-range feels really strong on the A45 and explains why the engine just keeps pulling to the redline. When you combine a wide torque band, with an early onset of torque, you end up with a very agile package.
When we also see how much more power/torque this turbo can provide further on, it makes the overall set-up even more amazing.
So what else can we find out?
Another advantage of the MAHA RR is that we can also capture and overlay other data, that is gathered at the time of the dyno run. For these stage of tests against Stage 1, we’ll access additional data direct from the ECU (via the ODB port) and feed these into the dyno hardware. Later on in future stages I’ll look at capturing all manner of data via software accessing the ECU directly (which will enable more information to be captured).
TEST 1 Boost Plot
The problem with logging via OBD is that the logging sample rate can be quite slow (hence why the plot is very angular). Also with boost, OBD is capped to around 1.55bar, so the plot levels out at this (the scale is in absolute, so you need to take a whole number off to get the boost pressure - i.e. 2.5bar absolute is 1.5bar boost). The graph looks like max boost is 1.55bar, which it won’t be in reality.
I’ll get these graphs refreshed with proper boost plotting, so we can see what the max boost is. I don’t even know what this is, as I wasn’t able to log it…. we’ll find out don’t worry.
Putting the above slight issue to one side…..
The first thing that “shocked” me when I saw the standard run boost graph, was the boost profile. I’m used to a car hitting peak boost just prior to peak torque and then trying to hold that boost through the mid-range, and then falling off towards the latter part of the rev range.
Not with the A45 it doesn't! However, once you start thinking about it (taking the torque graph into account), it all makes sense. The boost is profiled like this to keep the torque curve nice and flat, which aids driveability and potentially enables the top end power to be retained at a higher RPM. I also think this is an emissions “thing” as well…. we’ll see more on that when we look at the fuelling side of things.
The harder and earlier you “work” a turbo, the earlier (within the rev range) it can start to run past it’s efficiency, inturn pumping hot air. Taking the approach that AMG have, means you end up with a really good powerband…. ergo a quicker car on the road.
There was me originally thinking (as we’re told that this turbo is operating at 1.8bar as OEM set-up) that this turbo must be some monster technology to make 1.8bar at just over 2k and holding through the mid-range. Not at all….. AMG have just used a different approach to give the best powerband, and ultimately a quicker car. Nothing groundbreaking, but a really good approach in this instance.
As you can see by the boost plot, the mid-range is only running around 1.35bar. We’re seeing 1bar at a little over 2200rpm. In 4th gear on a dyno that is pretty awesome.
TEST 1 Ignition Plot
So here we have the standard ignition map. On it’s own it’s fairly irrelevant, but as we look at the differences of the before and after (tuning box), we’ll have something else to “inspect”.
The only thing worth saying is that you’ll be able to see how the ignition is ramped up as we gain revs on the standard set-up. Currently peak ignition is showing advance of 12degs @ 6k rpm.
TEST 1 Lambda Plot
Since this graph is showing what the ECU is seeing via OBD, this is from the lambda prior to the CAT. On new cars like the A45, this specific lambda sensor is pseudo “wideband”. This is much more accurate and quicker lambda sensor, than what we used to see in cars a few years back. I’ll tell you why this is important once we talk about the tuning box testing.
Like when I saw the boost curve, I was also quite shocked when I saw the lambda plot. The A45 likes to run very lean by the looks of it!
You can see by the graph that the fueling starts off rich as you come on boost, and then leans right out. Then gradually the fueling starts to richen back up again, until at peak power it’s about the level that you would normally aim for on a tune.
The leaner the engine runs, the hotter it runs and the cleaner the burn cycle….. which ultimately means less emissions. If you wondered why the A45 can achieve so good emissions, this will be one of the reasons. Obviously the engine is designed to run this hot, but I wouldn’t feel comfortable running a car this lean as a strategy moving forward (when we look at future mods for more serious power).
For me, this was another set of interesting data logs, which now start to explain quite a few things about the A45, but also gives us areas to “play with” in the future.
TEST 1 Road
There is no point in having a “Road Test” overview…… you all know how these cars drive in standard form. However, to date I have no OEM state of tune VBOX logs. I can capture this information if it appears prudent to do so, but I think there is enough information out in the wild, that we appreciate the OEM numbers (like 0-60 and 0-100mph etc).
When all’s said and done, the key thing we have here is a baseline to reference against, for any engine mods we decide to do hereon.
Full results from the Litchfield Tuning Box will be up within 24hrs!
28 February 2015, 05:57 PM
#50
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Apologies Ditch. There is a lot of stuff in that post that you guys would have already read on the other threads I've done.
I'm effectively copy and pasting what's going on the MB forums, so it has all the detail in it, as I don't know what they know or do not know at present.
The juicy stuff will be in tomorrows update.
I'm effectively copy and pasting what's going on the MB forums, so it has all the detail in it, as I don't know what they know or do not know at present.
The juicy stuff will be in tomorrows update.
28 February 2015, 11:02 PM
#53
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Brilliant thread, I don't mind admitting that there's still a ways for me to go before I understand it all....but I'm learning!
Out of curiosity and in relation to a particular point you made regarding the warranty with remaps and tuning boxes (my poor excuse for derailing the thread slightly), can a remap on a stock ecu be detected even if it has been restored to the factory setting at a later date (ie. does it have a log) or does it depend on the car?
Out of curiosity and in relation to a particular point you made regarding the warranty with remaps and tuning boxes (my poor excuse for derailing the thread slightly), can a remap on a stock ecu be detected even if it has been restored to the factory setting at a later date (ie. does it have a log) or does it depend on the car?
01 March 2015, 07:16 AM
#54
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Hi scoobyranger,
Glad you like the thread.
I suspect there are various ways that manufacturers can detect remaps, but the common one that I'm aware of is the "re-write" counter. Nearly, if not all, ECU's count (store) the times an ECU has been written to. Since service history will show if an ECU has received an update, it would be pretty obvious that some custom mapping has gone on (if the ECU count is 15, when the car has only received 2 updates from service).
There is a way round this though on some ECU's though.
Glad you like the thread.
I suspect there are various ways that manufacturers can detect remaps, but the common one that I'm aware of is the "re-write" counter. Nearly, if not all, ECU's count (store) the times an ECU has been written to. Since service history will show if an ECU has received an update, it would be pretty obvious that some custom mapping has gone on (if the ECU count is 15, when the car has only received 2 updates from service).
There is a way round this though on some ECU's though.
01 March 2015, 07:25 AM
#55
Apologies Ditch. There is a lot of stuff in that post that you guys would have already read on the other threads I've done.
I'm effectively copy and pasting what's going on the MB forums, so it has all the detail in it, as I don't know what they know or do not know at present.
The juicy stuff will be in tomorrows update.
I'm effectively copy and pasting what's going on the MB forums, so it has all the detail in it, as I don't know what they know or do not know at present.
The juicy stuff will be in tomorrows update.
01 March 2015, 10:12 AM
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Starting to get deeper 
I'll just wait patiently for part 2
I bet this thread must have made a few people raise an eyebrow, and no doubt they will be waiting in anticipation for the release of the tuning box findings.
It's good to mix things up
I'll just wait patiently for part 2
I bet this thread must have made a few people raise an eyebrow, and no doubt they will be waiting in anticipation for the release of the tuning box findings.
It's good to mix things up
01 March 2015, 10:25 AM
#57
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Thread Starter
TBH the majority are loving it, I suspect because this type of project approach hasn't really been done before for the A45.
There appears to be an element of misinformation out there at the moment, which is what happens, through no fault of any individual. Someone say's X on the net and suddenly it gets re-quoted, and becomes absolute fact.
The results are, shall we say, interesting.
There appears to be an element of misinformation out there at the moment, which is what happens, through no fault of any individual. Someone say's X on the net and suddenly it gets re-quoted, and becomes absolute fact.
The results are, shall we say, interesting.
01 March 2015, 10:36 AM
#58
Which in effect is no different to the Subaru scene some 10/15yrs ago, some of which still remains to this day, even now if you install a new brand of air-fresner in your Subaru you'll need a map tweak to make sure it's not effecting the metered air that the maf sees through the ventilation system. 
01 March 2015, 10:37 AM
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Which in effect is no different to the Subaru scene some 10/15yrs ago, some of which still remains to this day, even now if you install a new brand of air-fresner in your Subaru you'll need a map tweak to make sure it's not effecting the metered air that the maf sees through the ventilation system.
DAM