M&M

So let's not fight & just discuss this from a pure physics point of view. 1stly I must say that I am a huge E55 fan & am in no way comparing an E55 to an M3. This is just to work out some 60ft possibilties.

We have seen that E55's can do 1.8 60fts. Of course Improviz makes a good point that it has significantly more power & torque than an M3/C55.

BUT, it weighs 4200lbs. ALso, one can't really brake torque more than about 2200rpm (correct me if I'm wrong). So according to the dyno grpahs from this forum it seems that at that point the E55 has around 350 lb/ft on the wheels.

An M3 would rev to 4900-5000 on launch. At that point it's making 225-230 lb/ft to the wheels. I'll ignore that the M3 has shorter gears that work as a torque multiplier to the wheels.

But F=M*A. SO A = F/M. Therefore torque to the wheel divided by the mass would dictate the acceleration off the line & then HP would take over.

FOr the E55 4200lb / 300 lb/ft = 12 lb per lb/ft
For M3 3200lb/ 230 lb/ft = 13.92 lb per lb/ft

Of course the E55 will have much more traction issues & wheelspin more. But the point is the M3 should have the better 60ft also due to the fact that you can control wheelspin with the clutch without lifting off the throttle.

I would say a 1.8-1.7 60ft is possible on a very stick surface with an M3. I have no reason to doubt that a C32/C55 can do similar 60ft's given similar circumstances. Its simple physics & physics doesn't care about the badge. What the best 60ft a C32/55 has got on street tyres. I would guess about 1.9.

Improviz

As are your torque figures for the E55.

First off, MBUSA states for the E55: Net torque 516 lb-ft. @ 2,650 - 4,500 rpm So, let's assume an 18% driveline loss, giving peak rear wheel torque of 423 ft-lb starting at 2650 rpm. Are you seriously arguing that it's 75 ft-lb off a mere 450 rpm down from its peak?? Or are you suggesting that its driveline efficiency is about 68%?!?!

As to the M3: BMWUSA states for the M3: 262/4900 lb-ft . So, its max torque is 262, at the launch RPM you're claiming (with no proof) is possible without huge wheelspin, at which point you claim 225-230 to the wheels...giving a driveline efficiency of 86-88%.

Ridiculous.

M&M

Yeah wiseguy, look at the graoh of an E55 before 2600rpm. The torque is still building up & is not as high as at peak torque.

Dude, I didn't even factor in the fact that the M3 has shorter gears & LSD.

And yes you can rev to 5000rpm & get very litte wheelspin on street tyres.

I just wasnt one answer. What the best 60ft for a C32/55 on street tyres? 'Cos if its around 1.9 I'm gonna' prove you wrong big time.

Improviz

So here they are again, idiot:

First off, MBUSA states for the E55: Net torque 516 lb-ft. @ 2,650 - 4,500 rpm So, let's assume an 18% driveline loss, giving peak rear wheel torque of 423 ft-lb starting at 2650 rpm. Are you seriously arguing that it's 75 ft-lb off a mere 450 rpm down from its peak?? Or are you suggesting that its driveline efficiency is about 68%?!?!

As to the M3: BMWUSA states for the M3: 262/4900 lb-ft . So, its max torque is 262, at the launch RPM you're claiming (with no proof) is possible without huge wheelspin, at which point you claim 225-230 to the wheels...giving a driveline efficiency of 86-88%.

Ridiculous.

Bux

man you guys need to chill......whats next 0-120ft? both cars c32 and m3 are low 13 sec cars and it will go back and forth on who does less wheel spin off the line.

Improviz

Here is a dyno for an E55:

Which means that for M&M's idiotic wet dream to come true, in addition to the M3 having a driveline efficiency of 88% and tires made of super glue, the E55 would have to be down 130 lb-ft from its peak torque a mere 450 rpm down from where its peak torque starts. Again, ridiculous. It's a fantasy, nothing more.

Bux

ya a 1.7 is like an AWD launch

reggid

does anyone have test results from say

0-10mph
0-20mph
.
.
.
0-100mph

for both cars, ideally from the same source/magazine. You can then convert these times to a time to distance form instead of the usual time to speed from which they are given.
i.e
0-10ft
0-20ft
.
.
0-....ft

that way you can see the distance between the cars when the faster one has travelled 60ft (or the 1/4mile for that matter) and can find how long it takes both cars to reach that distance. Its a bit rough unless there are enough test points in which case its pretty good. I think i have some data of my local mags but it may take time to find.

TC32AMG

I think I am missing something here. All things being equal it is not how much torque you can put down, the limiting factor would be the coefficient of traction available from the tires.

The E55 has a slightly wider tire and would therfore have just a little more traction plus the added weight to plant the rear end. IF two identical vehicles were using the same tires and were the same weight but one was an auto and the other a stick, the stick could launch harder and have a better 60ft than the auto? I could see the stick as having less drivetrain loss but in the first sixty feet I find it hard to see a difference.

I also don't get how power braking is not advantageous as when you power brake you are actually applying/loading up as much power and torque that the front brakes/tires can hold and at the same time the maximum traction of the rear tires given that the stall speed of the torque converter is adequate as well which it usually is.

'Dumping' the clutch is similar except you are putting a shock to the drivetrain but in effect doing the same thing. Slipping the clutch I see as slightly less efficient becasue it has the human factor in modulating the power to the wheels, like backpeddaling on the gas with an auto.

Given all that, 1.7 is still hard for my friend to get in his modded S4 with a 5.5K rpm clutch dump he gets mid to low 1.8's he has done a few 6K+ dumps but it makes little difference and is murder on the drivetrain.

Another thing that makes it hard to get a low sixty foot is that with any car using low profile tires you do not have much sidewall flex if at all to help plant and launch the car and with the stiff suspension designed for road courses does not help either.

T

M&M

OK Improviz. Let's be civilised. What would you accept as a reasonable figure for an M3's torque on the wheels. Over here we are fining 15% drivetrain loss. Low profile tyres, 100% LSD & manual gearbox with short gears tend to help.

So let's say the M3 gets 220lb/ft to the wheels at 5000rpm. Does that sound fair? That's 17% loss which is too much in my book, but I'm tired of your excuses so I'll err on the conservative side to avoid your criticism.

So far we are on track? 220lb/ft at 5000rpm.

A C32 can only brake torque ro maybe 2200rpm. If I'm wrong please correct me instead of going on having a fit. Here's a dyno I found that goes as low as we require:

http://www.hs-elektronik.com/datenbl...s-c32-amg.html

It seems the C32 makes aroud 255lb/ft at 2000rpm on the engine. At the wheels let's assume the same drivetrain loss as the M3. HELL NO IT WILL NOT - SHORTER GEARS + MANUAL = LESS LOSS. BUT, I will humour you as assume the same loss just to keep you quiet. At 17% loss that works out to 211lb/ft on the wheels at 2000rpm.

I know the M3 is lighter, but once again I will assume they weigh the same. At the respective launch rpm for the cars, the M3 has more torque, LSD, wider tyres stock plus the ability to control wheelspin with the clutch. Please guys, is it not reasonable to assume all things being equal that an M3 can do slightly better 60ft's than a C32?

Now, hee's Ro0zy's timeslip with stock tyres:



BTW, great runs there Ro0zy. It seems C32's can do 1.9's easily. Now, forget M3's for a minute. I bet if you could put a manual 'box into a C32 you could get 1.8's maybe even high 1.7's under ideal conditions. The reason I say that is you could launch at higher rpm & feather the clutch.

So, I think I have a convincing argument based on facts. Note I am not saying any particular car is better than the other or whatever. This is just an observation on 60ft times.

Jon200

u said in your other thread you don't diss Mercs, now ur talking utter trash.

M&M

What are you on about. I said that if a C32/55 can do a 1.9 60ft (which it can) then Improviz is going to be in trouble 'cos I'm gonna's prove his theory wrong about M3's. What's wrong with what I said?

Improviz

Sorry, mate...if I had one inkling that you were here to engage in honest discussion, I'd press on, but the facts show your true intentions.

The fact is that you have produced no evidence that a 1.7 sec 60' time is possible in a "bone stock" M3 can do it.

M&M

Hahaha you lose. I knew this would happen. Have no excuses left excpet to attack me personally instead of discussing the topic. Then answer this. Is it possible for an M3 to do a 1.8 60 ft?

Improviz

Might I remind you, for about the 100th time, that your are arguing about a "bone stock" M3 (even though this link shows it was NOT bone stock)? And that I have told you that the only chance the M3 would have to *possibly* get a 1.7 60' would be if it was wearing drag radials or slicks??

Might I also remind you that when you posted the timeslip, you falsely stated (this makes about five lies I've busted you in in the past few days):Well, it might interest you to know that ro0zy was wearing Nitto Drag radials when he did the run from which you are posting the timeslips:

I.e., he wasn't "bone stock" at that point either, as he'd switched the OEM tires to the drag radials. Thus torpedoing your claim that the M3 could get a 1.7 "bone stock" (and makes it unlikely even with drag radials).

Your premise for this thread, your "proof", accepts as factual, with no proof provided, that an M3 can be launched on stock tires at 5,000 RPM without massive, time-robbing wheelspin.

Yet when Road & Track tested it, they stated that Off the line, the M3 delivered the best acceleration run using drop-clutch launches with the engine revving at 2500 RPM.

Finally, the graph you provided for the C32 plainly shows **370Nm*** (those little increments are each 40Nm, and the blue stock line crosses the 2,000 vertical line about 25% of the way up to the next increment) at 2,000 rpm, which works out to 272.91 ft-lbs, not the 255 you are claiming.

And *do* let us know when you've got some proof for your assertions.

M&M

I found more than one C32 that did 1.9 on street tyres on this forum. Do you dispute that or must I find the posts for you?

2ndly, the reason seasoned M3 owners can beat the mag times is EXACTLY because of what you posted. 2500rpm launch. HA! You don't own an M3 so let me tell what will happen if you do that on a sticky surface. YOU WILL BOG!

4500-500 is the way to launch an M3. Did I mention it has a 100% LSD & wider tyres than a stock C32.

C'mon this is getting painful for you. You are so caught up in your little mission to prove me wrong that you will soon start doubting your own Merc colleagues. I bet you gonna' say a C32 can't do a 1.9 60ft on stock tyres. 'Cos then you know an M3 can do a 1.8. So let me ask you for the millionth time. Do you think its possible for a stock M3 to do a 1.8 in perfect conditions?

Improviz

launch as its best time; in fact, it's rather ridiculous that you would even suggest such a thing (about par for the course, iow).

Here are the salient facts, which you skipped (as usual) from my last post. If you don't start addressing the points, I'm simply going to start pasting them into my replies until you do, to make the point that you're an evasive liar.

M&M

OMG! I can't believe I walked right past the evidence that's going to shut you own. Thanks for posting for me.

Ro0zy posted here: https://mbworld.org/forums/showpost....30&postcount=8

that he ran the Nitto drag radials & they made a difference of hundredths of a second (looks like 2 hundredths). PLease correct me if I'm wrong instead of calling me a liar.

Now that is in line witha we found here as well. The gains were negligible. If the C32 with narrower & smaller tyres & more torque gains hundredths on the 60ft, what will the M3 gain? The law of diminishing returns applies when you have a track that's very well prepped as the traction is as good as it gets.

Improviz

Perhaps ro0zy could speak to this specifically: he stated that he was able to hit a 1.9xx 60' time on the stock Pilots. I'd have to know what "xx" meant"; for example, if it's a 1.99, well, you wouldn't argue that that's the same as a 1.90, would you?

Here is his other run on the nitto drag radials: he did two runs, and got the following 60' / 1/4 mile times:

1.952 / 13.001 @ 107.98
1.972 / 13.118 @ 107.35

In the last run he did with the stock Pilot Sports, he ran a 13.2@104.9. But he didn't post the timeslip, only that his 60' was 1.9, which I suspect was certainly not a 1.90, but more likely 1.96+, i.e. closer to 2.00. However, ro0zy can comment to this...

ro0zy? Slip?

And M&M, I won't let you wriggle out of the prior claims you made with no proof. As long as you keep ignoring them, I'll post them here:

MiamiAMG

Dude, stop arguing with this guy. No matter what you say, in his eyes the M3 is the best & fastest car in the world. It's even faster off the line than an E55

M&M

Improviz, let's do this slowly. I know you don't own an M3 nor do you want to. But an M3 has max torque at 4900rpm. I has max power at 7900rpm. It is commonly acknowledged that for the best launch one must try to launch around the peak torque rpm. Between max torque & max hp would be best for max acceleration off the line.

In fact, most aftermarket launch control system like Racelogic would set the launch rpm to the max torque point. Now of course different surfaces play a factor. You can't launch the same on ice as you would on tar. So on a slippery surface maybe you don't want max torque getting to the wheels.

Maybe C&D got a good launch on their surface at 2500rpm. I could get a good launch at that rpm as well by dumping the clutch instead of slipping it to get a bit of wheelspin.

But on a good surface we see E55's with double an M3's torque getting good traction & 60ft's. So there's no reason why an M3 should have a problem as even at 5000rpm it has half the torque of an E55.

M&M

Hey Miami, an M3 is not faster than an E55, nor is it a better car than a C55. In fact it is inferior to a C55 in just about every dept. This discussion is about 60ft times & Improviz is not looking good. 1.9x for Ro0zy is good enough for me.

Improviz

...without excessive, time-robbing wheelspin. Witness for example Road & Track's test results for the Ford GT (pdf):

Engine's peak torque is spec'd at 4,500 rpm, but they clearly state that "just the right amount of wheelspin" was obtained at 2,500 rpm. Clearly, launching at higher revs gave too much spin.

I maintain that the M3 cannot obtain a 1.7 60' time on stock tires. You have theorized (mostly using logic full of holes, incorrect arguments, and falsehoods) that it can, but you have yet to prove it.

So, because the E55 can hit a 1.8, you think an M3 can hit a 1.7?? Fine, then I state because an E55 can hit a 1.8, a 325ci can hit a 1.5. I don't have any proof, so you'll just to take my word for it.

M&M

No what i said is if wheelspin is not a problem or the E55 (clearly as a 1.8 60ft shows), then wheelspin most definitely won't be a problem for the puny, torqueless M3. After all torque is what spins the wheels an M3 has 255/18" or 265/19" as stock.

Do you agree or you think an M3 will have more wheelspin than an E55 on the fast sticky tracks? C'mon I'm willing to concede that 1.7 seems unlikely unless on Nitto's if you concede that 1.8 seems possible for an M3 on stock tyres.

Improviz

Good, so perhaps you'll admit that your previous torque figures were wildly off the mark?

First, that's a ridiculous, untrue statement. All of them noted that they had to take steps to avoid excessive wheelspin.

Um, let's be clear here, chief: you're rather conspicuously dropping the "hundreths" column there. "1.8" means "1.80". The three E55 examples you provided were much closer to a 1.90 than to a 1.90:

The first, Marcus Frost, reported on seven runs. *ONE* run was in the 1.8x range, chiefly a 1.871, which as one would expect corresponded to his best 1/4 time of the day, 12.27 @ 113.89. His other 60' times were as follows: 2.263, 2.158, 2.147, 2.145, 1.937, 1.929. So, the one run was still closer to a 1.90 than to a 1.80. You will also note that he reported when running his 1.871 60' that Rather different than shocking the system with a high-rpm launch, innit?

The second, enzom, reported two runs: the first a 2.145, the second a 1.881. Again, closer to a 1.90 than a 1.80, right? One other guy did report a 1.84, but most are in the upper 1.8xx range.

And the third guy you reported, user DerekFSU, ran a 1.888.

SO, please dispense with the one significant digit. The facts show that they're mostly running more in the range of 1.90 than 1.80, so let's try to be a bit more accurate.

Now, let's get back to the point:

You are ignoring the fact that the E55 is a mid-to-low 12-second 1/4 mile car, bone stock. By which I mean that its enormous power and torque will have it moving one helluvalot faster for the second 30' than the M3 will be.

The fact is this: as you yourself have pointed out, you had no difficulty finding E55's in the 1.8xx 60' range, bone stock. But in looking around the M3 forums, very few get below 2.1xx or 2.0xx:

Here's one:

Another; best of 2.1:

Another, best of 2.1:

Another, with a best of 2.171:

This one got a 2.073, nearly a 2.1:

Three runs, one 2.04, the other two 2.07's

This guy got a 2.049:

And so on....if you go to the M3forum.net (where I notice you spend some time), and look at their timeslips page, you will see that all M3's whose timeslips are on the page are 2.0x and above.

You will also note that the ET's of these M3's are all very close to the magazine tests they've thoughtfully provided from Autoweek, Car & Driver (2), Motor Trend (2), and Road & Track.

So no, I'm not conceding a 1.8x, let alone a 1.80, for a stock M3, end of story.