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      01-02-2008, 08:35 PM   #55

Drives: e46 M3
Join Date: Dec 2007
Location: Earth

iTrader: (0)

Originally Posted by swamp2 View Post
Not sure I follow your "not sure". I am comparing the E46 M3 vs. E46 M3 CSL % torque gain at different rpm then applying simple ratio-ing to the E92 M3 case. The percent gain is absolutely different at different rpm.

At the rpm where each (E46s) have peak torque (4900) the torque figures are straight from BMW specs. The peak torque increase was (273-269)/269 = 1.5%. But developing more torque at higher rpms is more important than developing a great peak torque percentage increase. This is basically saying hp is more important than torque. Indeed the torque gains (as a percentage of base) at the rpm of peak hp are equal to torque gains (again on a percentage basis).

(360-343)/343 = 5% just as (239-228)/228 = 5%

Anything you are not sure of here?

So I agree with you that enhancements to the E92 M3 for modding or by BMW for the CSL will not do much to the peak torque. Yet I disagree that there is almost no torque to be had. One needs to qualify the torque curve not just peak figures, which seems to be what you did in your original post. BMW should be able to get at least 5% more torque at the rpm of peak hp, hence 5% more hp, through breathing enhancements alone. That would be 440 hp (441 for the sticklers and that is based on 420 hp not 414...). I'm guessing by raising the redline to 8500-8600 and/or by doing a bit better than the 5%, we will see 450 hp.
what I'm saying is they raised HP 360/343 ~ 5%, and they raised T ~ 5%
they did not yeild more torque...beyond the associated HP increase...
and I'm guessing they only got that at the top end...peak T increased by only 1.5%...
increased volumetric efficiency...

if they would have raised HP 5%, and torque 10%, then I would be impressed...the only real way to that is with compression (mep) or displacement, both of which remained the same...

do you have the factory csl power graph?