Slow 1/4 mile times...14.4 need help!
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Senior Member
Joined: Dec 2001
Posts: 251
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From: Seattle, WA & now Taipei, Taiwan
W211 E63
Slow 1/4 mile times...14.4 need help!
I ran the car 3 times Friday, 14.6 the 1st time with the car in D ASR on, 14.49 2nd time downshift to 1st gear ASR off + torque brake, 14.47 3rd time same without torque brake. The 60 foot time is about 2.5 +- ).1 sec and the trap speed is 100mph +- 1mph.
THe outside temp is about 82F and water temp is about 95C. Not much tire spin with ASR off and no spin at all with it on. 32lb of pressure on the tire. 3/4 tank, no spare, 18" Carlsson 1/6 rims, S03 tires, Texaco 92 octane gas......
I thought my car is not that fast since I first own it but it still dynoed at 290whp. So what is wrong with my times. I had expected to break into 14.00 at least.
Need help, thanks in advance!
THe outside temp is about 82F and water temp is about 95C. Not much tire spin with ASR off and no spin at all with it on. 32lb of pressure on the tire. 3/4 tank, no spare, 18" Carlsson 1/6 rims, S03 tires, Texaco 92 octane gas......
I thought my car is not that fast since I first own it but it still dynoed at 290whp. So what is wrong with my times. I had expected to break into 14.00 at least.
Need help, thanks in advance!
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Joined: Jan 2002
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Carlsson 1/6 + 3/4 tank of gas = mid 14's! This formula looks okay to me!!!
But I think even with a stock C32 with no mods, it varies from mid 13s to low 14s. There are many factors to it.... weather, tires, launch, the "mood" of yr engine (whether yr engine has been trained to do the 1/4 mile that day)....etc
But I think even with a stock C32 with no mods, it varies from mid 13s to low 14s. There are many factors to it.... weather, tires, launch, the "mood" of yr engine (whether yr engine has been trained to do the 1/4 mile that day)....etc
MBWorld Fanatic!
Joined: Feb 2002
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From: San Diego, CA
C32 AMG
I still think 14.6 is a little high, even with variances allowed. Did you dyno with the 1/6 rims on or before that?
Go back to the track, do some more runs on another day with the suggestions at c32life and see what happens. If you can't break 14 sec, then start wondering.
Go back to the track, do some more runs on another day with the suggestions at c32life and see what happens. If you can't break 14 sec, then start wondering.
Thread Starter
Senior Member
Joined: Dec 2001
Posts: 251
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From: Seattle, WA & now Taipei, Taiwan
W211 E63
Below is from roozy on the launch topic:
how i ran a 13.2
1)esp off
2)shift into gear 1 (and let it shift byitself)
3)no brake torque stuff for me
4)mash the gas but let off a little or the tires will just spin
5)let a little air out your rear tires.
-and before hand if your at a track and have time let the engine cool down and put a big ice bag over the SC. so the air inside gets denser
Roozy posted that he did not torque brake and he still got a 13.2 1/4 mile time. BTW, My 290rwhp dyno run was with the Carlsson rims! I did everything similar to what he said(except for the ice bag) in my 3rd run and the car only ran 14.3x.
how i ran a 13.2
1)esp off
2)shift into gear 1 (and let it shift byitself)
3)no brake torque stuff for me
4)mash the gas but let off a little or the tires will just spin
5)let a little air out your rear tires.
-and before hand if your at a track and have time let the engine cool down and put a big ice bag over the SC. so the air inside gets denser
Roozy posted that he did not torque brake and he still got a 13.2 1/4 mile time. BTW, My 290rwhp dyno run was with the Carlsson rims! I did everything similar to what he said(except for the ice bag) in my 3rd run and the car only ran 14.3x.
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Joined: Mar 2002
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.02 on 1/4
Ah, certainly no need to panic if you dynoed at 290. That is par for the course.
I believe Roozy's time is an all-time best, so it is safe to say that you won't match it without doing everything exactly right. BTW it is apparent that Roozy knows racing, it is safe to assume he didn't just go out and haphazardly make that 13.2.
Let's look at some factors that could likely make a difference:
Sea Level. Roozy lives in Houston. Where are you?
Ambient Air temp. Roozy ran in Winter, at night? you ran in 85degrees?
SC temp: Roozy iced his, you didn't.
Weight: Roozy probably stripped his car a bit, ran on empty, he weighs less than you by 50 lbs? All the weight adds up.
Wheels: lets assume Roozy ran on stock, you have heavier wheels. (Wheels may effect 1/4 more than dyno, dunno)
Octane: you can bet he ran race fuel, maybe 104.
The weight factors probably won't even enter into your dyno report. Maybe your dyno was run in the cool AM with a bunch of fans on the SC? And your 1/4 was run on an already hot "horse" in 85 degree weather? Was the gas the same for both?
My appologies to you and Roozy for making assumptions about what you and he did when I was thousands of miles away, but these are just some ideas to get you thinking.
Of course I am guessing but there is more to the equation than a dyno will show.
First places to look:
Do you know what your car+driver race weight was?
Octane
Temperature
PS one hint is, I believe you lost .5 sec by the 60 foot mark.
I believe Roozy's time is an all-time best, so it is safe to say that you won't match it without doing everything exactly right. BTW it is apparent that Roozy knows racing, it is safe to assume he didn't just go out and haphazardly make that 13.2.
Let's look at some factors that could likely make a difference:
Sea Level. Roozy lives in Houston. Where are you?
Ambient Air temp. Roozy ran in Winter, at night? you ran in 85degrees?
SC temp: Roozy iced his, you didn't.
Weight: Roozy probably stripped his car a bit, ran on empty, he weighs less than you by 50 lbs? All the weight adds up.
Wheels: lets assume Roozy ran on stock, you have heavier wheels. (Wheels may effect 1/4 more than dyno, dunno)
Octane: you can bet he ran race fuel, maybe 104.
The weight factors probably won't even enter into your dyno report. Maybe your dyno was run in the cool AM with a bunch of fans on the SC? And your 1/4 was run on an already hot "horse" in 85 degree weather? Was the gas the same for both?
My appologies to you and Roozy for making assumptions about what you and he did when I was thousands of miles away, but these are just some ideas to get you thinking.
Of course I am guessing but there is more to the equation than a dyno will show.
First places to look:
Do you know what your car+driver race weight was?
Octane
Temperature
PS one hint is, I believe you lost .5 sec by the 60 foot mark.
