Remapping improve MPG???
26 February 2010, 02:23 PM
#91
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I'm still struggling with the idea that the mapping Engineers at Subaru did not jump onto the fact that they can get their cars to higher mpg's ....
The fact is that they would have to sacrifice something to gain those mpg's - that would be a reduction in power - or a decrease in realibility ... none should be acceptable.
The fact is that they would have to sacrifice something to gain those mpg's - that would be a reduction in power - or a decrease in realibility ... none should be acceptable.
A custom remap is for your specific car. Every car will be different (ask any mapper). That is why mappers spend hours tailoring a map to your car and don't just download a stock map from the last car they did. (Although you would say that's how they justify charging so much, but you are slightly cynical, aren't you
).The only sacrifice I've had to make after the remap was making sure I only put 99 octane fuel in, as that is what it was mapped on.
26 February 2010, 02:23 PM
#92
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SSU with all due respect to your obvious automotive engineering skills, which you are yet to establish what qualifies you to pass your opinions as fact? 
The route that I took was from my house in Llanelli, A476 to Cross Hands, A48 to Carmarthen, A40 towards Haverfordwest, at Haverforwest take the B4548 (I believe) over the Preseli mountains, A486 (i believe) to Cardigan, A484 to Carmarthen, A48 to Cross Hands, A476 to Llanelli, total route 130 miles.
Both runs I left at approx 6.30pm, obviously I did encounter some other traffic en route but it was light - I could not recreate those road conditions.
Have you also yet grasped the fact that fuel used more efficiently equals better economy?
The route that I took was from my house in Llanelli, A476 to Cross Hands, A48 to Carmarthen, A40 towards Haverfordwest, at Haverforwest take the B4548 (I believe) over the Preseli mountains, A486 (i believe) to Cardigan, A484 to Carmarthen, A48 to Cross Hands, A476 to Llanelli, total route 130 miles.
Both runs I left at approx 6.30pm, obviously I did encounter some other traffic en route but it was light - I could not recreate those road conditions.
Have you also yet grasped the fact that fuel used more efficiently equals better economy?
What you fail to grasp, and I am trying my best, is that your two 130 mile trips WERE different .... different enough to account for a 1.4mpg increase.
Hell, even working it out would account for half of that error!!
You must see that, surely?
26 February 2010, 02:31 PM
#93
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I think it has already been suggested that the standard map is a safe/ slightly overfuelling map, so that it will be ok for every car off the production line running in every EU country's climate on 95RON fuel (or possibly lower).
A custom remap is for your specific car. Every car will be different (ask any mapper). That is why mappers spend hours tailoring a map to your car and don't just download a stock map from the last car they did. (Although you would say that's how they justify charging so much, but you are slightly cynical, aren't you).
The only sacrifice I've had to make after the remap was making sure I only put 99 octane fuel in, as that is what it was mapped on.
A custom remap is for your specific car. Every car will be different (ask any mapper). That is why mappers spend hours tailoring a map to your car and don't just download a stock map from the last car they did. (Although you would say that's how they justify charging so much, but you are slightly cynical, aren't you
).The only sacrifice I've had to make after the remap was making sure I only put 99 octane fuel in, as that is what it was mapped on.
They certainly did not spend hours on mine!!! Mine took about 30 mins!! They download a stock map and tinker it to suit and take in any mods etc
26 February 2010, 02:37 PM
#94
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A custom remap is for your specific car. Every car will be different (ask any mapper). That is why mappers spend hours tailoring a map to your car and don't just download a stock map from the last car they did. (Although you would say that's how they justify charging so much, but you are slightly cynical, aren't you)
Of course, the mapper will need to spend hours at a job .... to spend the required 25 minutes downloading a known map would have eveyone demanding their money back!
Failure to use Number 2 pump will render the map useless, you will need a new one!! ..... Have it mapped for a Number 2 and a Number 3 Petrol Pump
.... ohhh, yes, that will be another stonking amount of dosh too!! Not sure what warranties the mappers offer?, it used to be ZERO warranty - I cannot imagine that's the case these days of blown engines and holed pistons?
I wonder what warranty they would offer on their re-map if it was done on a car with delivery mileage? Would it be the 3 years Subaru warranty, extendable to 5 years and beyond? ................. If they won't warranty a new car you have to ask why.
Last edited by SunnySideUp; 26 February 2010 at 02:40 PM.
26 February 2010, 02:37 PM
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26 February 2010, 02:49 PM
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SunnySideUp I was under the impression you uprated a fuel pump so it delivers consistent pressure throughout the full range of your engine, ie high revs. Doesnt the standard one start to lose pressure at this point hence you lose power?
26 February 2010, 02:53 PM
#97
Tune a exhaust system right and it can act as a crude form of EGR (exhaust gas recycling), basically some exhaust gases remain in the combustion chambers.
What that does is reduce the amount of oxygen available for combustion. The result is less fuel is required to maintain the correct air fuel ratio (as there is less oxygen). The price, of course, is reduced power.
26 February 2010, 02:58 PM
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Thats why I waited until my warranty was nearly up!! Clearly getting a car remapped is by far the simplest method of obtaining more power you dont even need a spanner for flip sake but clearly I dont believe the car can be as reliable as the standard map!! In my case I am putting out 350lb/ft torque as opposed to 236 lb/ft so this is putting alot more stress on the gearbox, clutch etc. Its like everything in life there are positives and negatives.
26 February 2010, 03:02 PM
#101
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It's just an engine, it's not rocket science (that's where I would come in!).
What you fail to grasp, and I am trying my best, is that your two 130 mile trips WERE different .... different enough to account for a 1.4mpg increase.
Hell, even working it out would account for half of that error!!
You must see that, surely?
What you fail to grasp, and I am trying my best, is that your two 130 mile trips WERE different .... different enough to account for a 1.4mpg increase.
Hell, even working it out would account for half of that error!!
You must see that, surely?
As I have already stated I could not recreate the exact traffic conditions but then again neither could you
, what I could recreate was the route, time of day and to a certain extent the weather conditions. 
I had my Hawkeye remapped to free some of it's potential and not MPG but that was a welcome bonus mainly due to the characteristics of the power delivery being improved especially in the mid range performance.
My current Impreza an S202 even on standard form is 316bhp which is an improvement on the standard Subaru map and this is carried out by STi themselves, and yes it is fitted with an uprated fuel pump fitted at the factory.
26 February 2010, 03:09 PM
#102
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Depends on the standard map 1929... The 2008-2009 map was found to be flawed at the top of the rev range.. Subaru do not always get it right first time all the time.
A custom map (not nessesarily a more powerful map, just one fine-tuned to your engine) is the safest way to ensure the car is running correctly. Any increase in power mind you is obviously at the owners risk.
This is when the advice and skill of the mapper is paramount... I'd rather have the car take 2 hours to map and be right, than 30 minutes to produce the same power, but grenade after 2000 miles
The extra time taken is for testing, I'm sure Dunc could have mapped my car quicker, but we did it slowly, progessively, with safety margins built in at every point... when he was happy with that level, he'd then add a bit more... and the testing starts again... this cannot be done 100% in 30 minutes without taking huge shortcuts and thus risks... and if it goes bang.. it's your bill.
That 1st "already tweeked map" your mapper loaded up could have easily damaged your engine....a very risky procedure..non of the mappers I've seen have done that..and I'd consider myself lucky, not infer the mappers are taking the mick.
A custom map (not nessesarily a more powerful map, just one fine-tuned to your engine) is the safest way to ensure the car is running correctly. Any increase in power mind you is obviously at the owners risk.
This is when the advice and skill of the mapper is paramount... I'd rather have the car take 2 hours to map and be right, than 30 minutes to produce the same power, but grenade after 2000 miles
The extra time taken is for testing, I'm sure Dunc could have mapped my car quicker, but we did it slowly, progessively, with safety margins built in at every point... when he was happy with that level, he'd then add a bit more... and the testing starts again... this cannot be done 100% in 30 minutes without taking huge shortcuts and thus risks... and if it goes bang.. it's your bill.
That 1st "already tweeked map" your mapper loaded up could have easily damaged your engine....a very risky procedure..non of the mappers I've seen have done that..and I'd consider myself lucky, not infer the mappers are taking the mick.
Last edited by scooby L; 26 February 2010 at 03:22 PM.
26 February 2010, 03:25 PM
#103
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I am cynical whenever I hear poppycock like 'every car is different' ... that may have been the case 30 years ago, maybe 20, not now. Everything is so tightly controlled that they are, to all intents and purposes, the same.
And if the mapper told you to only use the number 2 pump at the petrol station - you would believe him
Failure to use Number 2 pump will render the map useless, you will need a new one!! ..... Have it mapped for a Number 2 and a Number 3 Petrol Pump
.... ohhh, yes, that will be another stonking amount of dosh too!! Not sure what warranties the mappers offer?, it used to be ZERO warranty - I cannot imagine that's the case these days of blown engines and holed pistons?
I wonder what warranty they would offer on their re-map if it was done on a car with delivery mileage? Would it be the 3 years Subaru warranty, extendable to 5 years and beyond? ................. If they won't warranty a new car you have to ask why.
2) Are you saying that there is no difference between running a car on 99RON as 95RON and having a car optimised to run on 99 is nonsense?
3) I had mine mapped while still under warranty nearly 3 years ago. Nothing has broken. It is now nearly 5 years old. Having a remap doesn't automatically mean you will need regular rebuilds.
Also, your issue with CannonFodder's mpgs: Surely the important point is that the increase in power did not significantly affect the fuel consumption.
26 February 2010, 04:47 PM
#104
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That is actually wrong, back pressure via a restricted exhaust, if done correctly can improve MPG;
Tune a exhaust system right and it can act as a crude form of EGR (exhaust gas recycling), basically some exhaust gases remain in the combustion chambers.
What that does is reduce the amount of oxygen available for combustion. The result is less fuel is required to maintain the correct air fuel ratio (as there is less oxygen). The price, of course, is reduced power.
Tune a exhaust system right and it can act as a crude form of EGR (exhaust gas recycling), basically some exhaust gases remain in the combustion chambers.
What that does is reduce the amount of oxygen available for combustion. The result is less fuel is required to maintain the correct air fuel ratio (as there is less oxygen). The price, of course, is reduced power.
26 February 2010, 04:48 PM
#105
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I think you lot are great .... you give me hours of challenging thought and debate, you go your own way and tinker with your pride and joys ..... and do what you believe in, I salute that.
But I do really struggle with the concept of buying a car you don't want (if it was what you wanted it, you wouldn't change it) .... I buy a car which does what I want it to do.
I don't buy a WRX and mod it to 330BHP ... I go out and buy a 330s.
But I do really struggle with the concept of buying a car you don't want (if it was what you wanted it, you wouldn't change it) .... I buy a car which does what I want it to do.
I don't buy a WRX and mod it to 330BHP ... I go out and buy a 330s.
What you are trying to understand is modding, and you just don't get it. Your own logic does not modify as you don't want or need to. The thing is, we do. lol. It wont make sense to you! It just wont! There does not have to be any justification nor proof of requirement or improvement. I just bought new wheels, i don't need em, i WANT them! Hahaha, I am addicted to modding my car.
26 February 2010, 05:24 PM
#106
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(By the way, I work with jet engines and even these have variable performance / fuel efficiency!)
While a remap on an otherwise stock car might not give a noticeable improvement in mpg, a remap on a car that has had intake / exhaust mods can take advantage of those mods and vary the fuelling accordingly.
Yes, at high revs, the engine will use more fuel in order to get more power, but at lower engine speeds, the map can be fine-tuned to match the improved induction / exhaust systems.
Therefore, with a remapped car - driving flat-out - worse mpg, BUT, normal mid-rev day to day driving - BETTER mpg!!!
My car gets about an extra 20 to 30 miles to a tank on the replacement map (about an extra 10% more miles per tank) and the engine runs more smoothly too!! It DOES work!
26 February 2010, 07:06 PM
#110
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So, the answer to your question is, no.
26 February 2010, 07:15 PM
#111
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Jealous? No my friend I'm not jealous at all - I can have pretty much whatever I desire in life ...... but, I make every single penny work for it's keep!
I haven't had a re-map ..... I haven't had sex with a donkey either, you don't always need to experience something to know it's not for you!
26 February 2010, 07:17 PM
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26 February 2010, 07:24 PM
#114
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Depends on the standard map 1929... The 2008-2009 map was found to be flawed at the top of the rev range.. Subaru do not always get it right first time all the time.
A custom map (not nessesarily a more powerful map, just one fine-tuned to your engine) is the safest way to ensure the car is running correctly. Any increase in power mind you is obviously at the owners risk.
This is when the advice and skill of the mapper is paramount... I'd rather have the car take 2 hours to map and be right, than 30 minutes to produce the same power, but grenade after 2000 miles
The extra time taken is for testing, I'm sure Dunc could have mapped my car quicker, but we did it slowly, progessively, with safety margins built in at every point... when he was happy with that level, he'd then add a bit more... and the testing starts again... this cannot be done 100% in 30 minutes without taking huge shortcuts and thus risks... and if it goes bang.. it's your bill.
That 1st "already tweeked map" your mapper loaded up could have easily damaged your engine....a very risky procedure..non of the mappers I've seen have done that..and I'd consider myself lucky, not infer the mappers are taking the mick.
A custom map (not nessesarily a more powerful map, just one fine-tuned to your engine) is the safest way to ensure the car is running correctly. Any increase in power mind you is obviously at the owners risk.
This is when the advice and skill of the mapper is paramount... I'd rather have the car take 2 hours to map and be right, than 30 minutes to produce the same power, but grenade after 2000 miles
The extra time taken is for testing, I'm sure Dunc could have mapped my car quicker, but we did it slowly, progessively, with safety margins built in at every point... when he was happy with that level, he'd then add a bit more... and the testing starts again... this cannot be done 100% in 30 minutes without taking huge shortcuts and thus risks... and if it goes bang.. it's your bill.
That 1st "already tweeked map" your mapper loaded up could have easily damaged your engine....a very risky procedure..non of the mappers I've seen have done that..and I'd consider myself lucky, not infer the mappers are taking the mick.
Last edited by scooby1929; 26 February 2010 at 07:25 PM.
26 February 2010, 07:26 PM
#115
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Difference is, I will be able to resist .......................... you, mapper lover and waster of money, may not be able to!
26 February 2010, 09:17 PM
#116
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I must admit I am on the same line of thinking as SSU on the remap front. I have two Subaru’s - an import and a UK. I have no probs mapping the import as there is the safety factor to consider i.e. accommodating for the poorer UK fuel.
Initially tempted by a tweak to release more power from my UK car, I would rather stick with the Prodrive map it comes with and sleep sound with the knowledge it is not being pushed too much and that the reliability will be good.
Initially tempted by a tweak to release more power from my UK car, I would rather stick with the Prodrive map it comes with and sleep sound with the knowledge it is not being pushed too much and that the reliability will be good.
26 February 2010, 10:24 PM
#117
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lol didnt cross me mind but to get back to the point and leave your sick tendancies behind after a remap i have been getting between 24 when driven hard and 26-27 when not mpg whereas before the remap i wasnt getting 20 even on longer cruises but you have to take into consideration the age and wear an engine has had things expand, contract and are bored out over time and use so each remap should be set to a specific car whereas at factory there all the same.
so in some circumstances what you are saying is correct and you will loose mpg a mate of mine recently had a map and his for sure went down but i know a lot of people that have got more mpg what you have to consider is that every engine is slightly different.
but we drive subarus in the first place so mpg isnt what we was thinking as we bought them and im damn sure we look for extra mpg when were modding
so in some circumstances what you are saying is correct and you will loose mpg a mate of mine recently had a map and his for sure went down but i know a lot of people that have got more mpg what you have to consider is that every engine is slightly different.
but we drive subarus in the first place so mpg isnt what we was thinking as we bought them and im damn sure we look for extra mpg when were modding
27 February 2010, 09:32 AM
#118
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I haven't had a re-map ..... I haven't had sex with a donkey either, you don't always need to experience something to know it's not for you! [/QUOTE]
SSU you would be very surprised what a donkey can offer, You must look them in the eye, talk to them softly and be gentle. you will never turn back, regarding the remap (don't know) but donkeys (oh yes) 
[/QUOTE]SSU you would be very surprised what a donkey can offer, You must look them in the eye, talk to them softly and be gentle
. you will never turn back, regarding the remap (don't know) but donkeys (oh yes)
27 February 2010, 10:24 AM
#119
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I do have to add to this thread though, the only problems i have had with my car have been the parts that have been added!!! The Subaru had been an awesome car. LOL.
So for SSU, here is my list to make you laugh, StopTech brakes - in the bin; Eibach springs - broken and in the bin; Several back boxes - too loud, too quiet, in the shed or sold; Alignment done on car, 4 times, LOL, yes 4 times; WRX TMIC - swapped for STI one so in the shed; WRX bonnet scoop - swapped for STI one so in the shed.
So, SSU, you stick with your reliable standard car and I will keep finding excuses to waste my money on ever more expensive upgrades! Hahahahaha.
Have fun!
So for SSU, here is my list to make you laugh, StopTech brakes - in the bin; Eibach springs - broken and in the bin; Several back boxes - too loud, too quiet, in the shed or sold; Alignment done on car, 4 times, LOL, yes 4 times; WRX TMIC - swapped for STI one so in the shed; WRX bonnet scoop - swapped for STI one so in the shed.
So, SSU, you stick with your reliable standard car and I will keep finding excuses to waste my money on ever more expensive upgrades! Hahahahaha.
Have fun!
27 February 2010, 02:07 PM
#120
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I haven't had my tracking done once!!
In 10 years and 98,000 miles!!
Every 2 years I change the Tyres - everytime they are worn pretty much evenly.
No need to mess about with what Subaru provided
In 10 years and 98,000 miles!!
Every 2 years I change the Tyres - everytime they are worn pretty much evenly.
No need to mess about with what Subaru provided