Shaun

One of the chat rooms a few of us natter on, appears to evolve around comparing and discussing performance data.

We must spend hours "debating" each others figures, what tyre pressure we use, what weight we are, how many craps we've had and who's king of the performance league!!! lol However, once in a while we actually discuss some meaningful stuff. At times having revelations about what's what.

I have recently acquired data from a mapped C63 (circa 520bhp), and a standard FL A45. The outcome of all of this latest data gathered really is interesting.... to the point that I feel quite depressed now. lol

When comparing dyno graphs, drag times, 0-60 runs etc etc, we tend to totally ignore real world comparisons. Even in-gear times don't mean a fat lot on their own. Something that is utterly measurable by your own eyes, is how much a car pulls ahead of you, or you pull ahead of another car on the road. This is one area, that up until now, I've completely ignored (and others) in any data comparisons that I've done...... it's probably one of the most relevant measures for our playful blasts on the road.

Below is a VBOX graph of three cars:

My A45 - Red Lines
C63 (520bhp) - Green Lines
Standard FL A45 - Blue Lines



The graph plots speed and distance travelled against time, for a run that is measured from 65-120mph. A good area for us spirited blasters.

The upper lines are speed against time and the lower lines are distance travelled against time.

You can obviously see that the C63 is clearly faster and covers more ground than the other two. As you can see my car is faster and covers more ground that the FL.

No real surprises here at all..... but what does this really mean. Now comes the reality shocker!!!

The table below shows the speed & distance difference between the three, when the C63 had hit 120mph.

Ignore the speed comparison....... look at the distance travelled.



My A45 is 27ft behind the C63.
FL A45 is 51ft behind the C63.

Mmmm.... that sounds quite a lot of "feets". But what does that REALLY mean!? Hold on, let's convert that to A45 car lengths.

So:

My A45 is 1.9 A45's behind the C63.
FL A45 is 1.7 A45's behind mine.
FL A45 is 3.6 A45's behind the C63.

Unless I'm missing something, all these amounts are paltry in the real world imo.

Sure the C63 is pulling hard and will continue to pull hard. The gap is/will widen.

This thread isn't really about how close/far a tuned A45 is, it's about what all the numbers mean in context.

Not a fat lot on the road in scenarios that many of us most likely encounter.

Put it this way..... I'm suddenly going off the idea of modding mine any further. There appears to be little point unless I chucked an extra 150+bhp into it, which isn't going to happen.

Tidgy

The reality is what's the price difference? sounds snobbish I realise, but if you compare a 100k car to a 40k car there's no real surprise what comes out on top.

But chuck 20-30k at it and your still 30k under the price of the 100k and prob find your are now out performing it.

joz8968

iTrader: (13)

steve05wrx

Hi,
A lot of how a vehicle performs on the road - especially in a "race" situation depends on the levels of risk that each person is prepared to take, along with weather & road conditions, tyres, grip etc.
Many slower cars have "beaten" me in a country lane "race" because they are prepared to take stupid risks that i won't.
You need to simply balance your needs for a distinctive, individual vehicle against the amount of money you are prepared to spend getting that vehicle the way you like it.
I am currently driving a big, heavy ML63 that has the optional performance pack and puts out 557hp as standard.
To date, I have never lost a traffic light drag race in Abu Dhabi or Dubai against a wide range of cars. This is for two reasons - 1) the car is amazingly quick in sport mode and covers 0-60 in 4.2 seconds (not bad for such a big vehicle) 2) I practice a lot and have got the red to green (no Amber here!!) getaway off to a fine art.
The differences in the graphs above can partially be mitigated by better or worse drivers and it would take a lot more hp difference to ensure that even a bad driver always had the edge.
Cheers
Steve

Shaun

This isn't about price..... this is all about what a tenth here and a second there really means. In the real world.... diddly squat in reality.

I was looking at this from a "further mods" perspective on my A45, which doesn't appear to be worth it. I'd need to go bigger turbo next, new manifold and all sorts of potential pain with the transmission. Even taking mine up to 500bhp wouldn't yield me any great "real world" benefits..... unless I'm hell bent on ensuring my car makes up that 1.9 car length. That's the reality!!

Dyno graphs, 0-60 and quarter times are one thing...... the real world for every day driving is clearly something else.

JGlanzaV

iTrader: (3)

But does it matter what other people do?

Mod your car for your benefit and **** everyone else....

dpb

Hilarious thread , iv still no idea what its about

nothing to do with cars I suspect

Shaun

I should have known better than putting some "reality" discussion up on here.

Perhaps the maturity of MB ownership is really getting to me now.... I must throw the baseball cap away and put the flat one on.

ALi-B

iTrader: (1)

The point of modding I believe is down to a few factors:

1) to make it go faster
2) to make it feel faster

Or for the tarts:
3) to make it look and sound faster

All three apply in varying degrees, however In this case we'll ignore 3) for now

Option 1) was always my prime objective, but as I got older I've ended up doing option 2) more, with more focus on getting a car to handle/behave better on the twisty bumpy back roads.

As there is always someone somewhere with something faster or more willing to throw money at something to make it the fastest, I'm just not competitive like that anymore- stick me in a kart race and that mentality does change though -level playing field

ALi-B

iTrader: (1)

Oh yeah, did you ever manage to get the VNT turbo working, Shaun?

Shaun

Not sure what you mean mate?

ALi-B

iTrader: (1)

I thought you were looking into using a variable nozzle/vane turbo setup....https://www.scoobynet.com/1019636-a4...-coming-2.html


Just wondering if there was any follow up to it, and what turbo you ended up going with.

ScoobyDoo555

FWIW Shaun, I get what you're saying. I did a similar real world thing with a my car and a few other (better) cars - no data: just visual observations.

This was against a Ferrari 360 Challenge race car (!), 996 Carrera4 (3.6l) , and my 996 Carrera 4 (3.4) with a few breathing and engine mods.

The Ferrari was of course, the quickest, but not *that* much more (CAVEAT - at normal everyday driving speeds) - mine has had a LOT spent on it (both due to repair and "whilst we're here" mentality). The 2 Porsches were quite evenly matched - different gaps. BUT we're talking fractions of car lengths. ie nothing in it at all - a lot of money of a small gap imho!

My conclusion was the same (might also be my age now! ) - if I want a Ferrari-beater, I'll buy one.
To those that enjoy the whole process of the build and pursuit of better figures, great - I enjoy reading and watching the progress.
But for me, my car is quick enough at the moment (circa 340bhp). Sounds and looks great (I accept that beauty is in the eye of the beholder!) and it's a realised boyhood dream.

When funds allow, the next stage up will be something Italian Although the wife may dictate a new house first

Dan

Shaun

Ali,
Gotcha..... still on the OEM turbo. My next step was to bang on an EFR.

Dan,
Someone that understands what I was trying to put across!!!

I have no problems with modding a car to make it faster/quicker/more exciting. The problem for me is the added risk, stress and cash to take mine to the next level.... which I don't think will provide any great real world benefit for me.

joz8968

iTrader: (13)

I got what you're saying from your first post, from the get-go...

We hear of it in threads on here all the time:
"...so I had a little 'play' last night with a [insert 'lesser' car here] and was really surprised to be beaten...yada, yada..."

This aspect of different power (and power-to-weight!) levels translated into real world 'gains' on the road has never been lost on me (since I got into performance cars - back when I passed my test!) and experiencing it on the roads for myself.

As Ali says, there's ALWAYS a bigger fish, so you may as well mod your car to how you like it to 'feel', and therefore making it more enjoyable - for ONESELF - to pilot.

Shaun

I'm not sure you do get what I'm saying mate.....

This has nothing to do with other quicker cars or getting beat by them..... it's about the realisation of what levels of increased power actually relate to on the road.

The comparison given was just a reality check, and a bloody good one.

I've been hell bent (with this car) on quarter times, in-gear times and power curves.

I wanted to look at the next step which was taking it up to 500+bhp, to bring those times down.... which logically speaking it should do. However, outside of those disciplines the benefits to me as a road car are going to be minimal.

In my craving for every last 10th, I lost the reality of what that means on the road. This is a road car for having fun it, not a drag or track car where every 10th counts.

joz8968

iTrader: (13)

Okay. Of course I get that.

Tidgy

Very few people can really get the full potential out of the car, despite what lot of poeple will claim, also on the road its rare you can push it to that limit anyway.

stevebt

iTrader: (8)

The reality of power is for each step further you go down the path of higher power you are going to stress out some parts you didn't expect to and there will be higher costs. Real world driving is different to 1/4 mile as it will depend on your gear you are in and what revs you are sitting at before flooring it. Without a doubt I can say any money spent on power will be wasted come resale So all depends on do you want a modded A45 with £20k thrown into it or a C63 with just a remap

lozgti1

Ok,I am in the 'I have no idea what on earth this is about' brigade.

Post 1 made my head explode.lol

john banks

I reckon if you have about 300 HP more than the other car it can be difficult to know if they are accelerating at all. If I can spin four wheels just by pressing the accelerator in a straight line whilst rolling in 3rd gear in the dry on good tyres (somewhere in region of 1000Nm) then I would need a good reason to tune more if it reduced that response.

Paben

iTrader: (5)

The occasional encounter on a long stretch of empty dual carriageway is one of the few times an outright power advantage will make itself felt, assuming both drivers are prepared to ignore the law and just let both cars go at full power. However, maximum 'sensible' pace on a typical country road (i.e. not prepared to die) means a well driven hatch can match the pace of almost anything.

Saxo Boy

Performance cars can be stacked a lot closer in drag races than you might instinctively think. The term "blown away" is wildly overused IMHO. Any race that's worth having (i.e. where there isn't an obscene advantage) will usually only gift 1-4 car lengths to the victor.

Typically, you need a very considerable p/w/r advantage to open up serious distance. From my own experience three scenarios stick in my mind as a serious *** whooping.

1. I raced a e46 M3 down a slip road in my VTS and it pulled out 3-4 lorry lengths.
2. I raced an e46 M3 up a slip road in a 400+bhp classic Type-R and the scooby pulled several lorry lengths
3. My personal favourite, I exited a roundabout behind a R33 GTR in the S2000 ready at 7500rpm in 2nd gear. He nailed it and so did I. 10s later the gap could be measured in football pitches. I have no idea what it was running, but it was monster power

In each of these scenario's there is probably 100bhp per ton or more in favour of the victor. However, I've also raced e46 M3 and S2000 and the Honda gives up no more than a few car length because they are more closely stacked in p/w/r terms (190 vs 225 ish)

As a final fly in the ointment, all these comparisons are from before the explosion in popularity of DSG/DCT transmissions. They are a whole new element to consider and sway things considerably. For example, the new (manual) Focus RS (345bhp) lost a hastily arranged drag race vs a (295bhp) DSG Golf R with the difference in shifting speed cited as the reason. Much of the reason the cars like the A45 AMG can post sub 10-second 0-100mph runs with basic mods is their gearbox. The actual p/w/r is often nothing particularly mental.

Devildog

Absolutely

And in real "real world" situations those 1.9 car lengths could easily be negated or doubled by something as simple as who got the jump on getting the power down first. Further negating the need to spend more an more in the quest for the ultimate numbers.

So you could spend £'000's to gain a tenth on a drag strip and see zero discernible difference on the road. In fact, you might even end up slower due to overall driveability.

That's nothing new though Sean, is it? (well, clearly it is to you )

In fairness - don't beat yourself up too much. After all - what you set out to do was see what could be achieved and at what cost. If you'd realised that after a couple of simple mods your car was as "real world" fast as a C63, we'd not have had the enjoyment of following your progress

Shaun

It was really the "realisation" about what an additional 50bhp would yield me, which in all honesty has been focussed around what it would do on the dragstrip. The problem really is that the transmission is meant to be the weak link..... if not I'd be contemplating throwing +100bhp at it. Then I'd start to go down the path of a car that loses elements of driveability. I didn't really spend this cash on a nearly new car to do that.

It's just the reality stepping in, which has been the downer. Reality normally does that though doesn't it! lol

Of course........ I'll probably still end up doing it mind you! Ha

urban

iTrader: (1)

I see a C63 on Shaun's wish list

Shaun

Not at all mate, as not really my cuppa tea.

I did look into getting a new RS6 though over the past few weeks. Remap and exhaust.... Boom, 700+bhp and an easy 10s quarter! lol

Won't fit in my garage though which is a "must have" criteria unfortunately.

Falsey

The critical aspect for me in modifying my past cars is "how does it feel?"

You could spend a lot of money and a lot of time making just about any bucket a rocketship or grip monster, which may or may not pay dividends if you are a track man chasing the tenths in competition.

What has always been my primary concern is how is my car now going to perform on the road? The one time I lost sight of that was with my Focus ST. Its so easy to liberate performance from one of those that I felt like I was obligated to. A few months down the line I had a ~300bhp ST that I could barely have fun with. It was a lot faster than a standard one, and a lot faster than most stuff I encountered on the commute, but it was not a pleasurable experience because it was a pain in the **** to extract the performance most of the time (although I admit that driving through the tunnel and popping and banging never got old) and it ate tyres faster than I could fit them.

My 200SX after that I completely avoided the power mods, I got sorted suspension, wheels, tyres, clutch, and fully reconned the existing power plant and that was ace. It was like a go kart despite clearly being slower than the ST, and probably in reality barely faster than my old 118d

Modding the car is fun, but at a point you are chasing tiny tenths of seconds and constantly chasing the performance bottleneck. Ive mellowed out into a 'why bother' sort of attitude since the ST. Every mod Ive put on to cars since has been either OEM+ or purely for experience benefit rather than headline figures. Cant say Ive had any bother with it.

Paben

iTrader: (5)

I suspect that modifying road cars is similar to bodybuilding; arguably better looks, more power and considerable bragging rights but otherwise of no practical use.

hodgy0_2

I have just returned from a trip to the Alps in a Ferrari 612, which apparently has over 500bhp

We were obviously pretty much the fastest thing on the road, but if another car really wanted to keep up you had to "try" before you pulled away

In fact I had to accelerate quite hard to pull in front of an Audi Q7

So i agree in the real world it is quite hard to show a dramatic difference


What I would say is that with that much power it is very easy/relaxing to maintain a high speed (we averaged 81 mph over 540 miles)