Quote:
Originally Posted by HighandDry
The key is the area under the torque curve and not the peak torque.
Having a car with high RPM's (M3, F430, GT3, etc) allows greater torque multiplication via gearing, which allows more work over time.
Having a car with more RPM's to work with allows it to have a mechanical advantage. The higher torque/lower HP car will pull away initially. As the car with higher torque/lower HP shifts into 2nd, the lower torque/higher HP car will start pulling away, because it's still in 1st gear. In 1st gear, it's putting down much more overall torque.
That's why a F430 can achieve a trap speed of 120 mph for a relatively low torque car. The above is also the reason F1 race cars have a pretty low torque of 300, but a HP of 900 and a redline of 19,000.
The thing slowing the M3 is it's weight.
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Its actually the power curve that is meaingful and only looking in the area within the 2-3k RPM's worth of the powerband which the car is in during maximum acceleration. ie. Looking under 6k for the m3 is useless when comparing its full-out performance. Daily driving ability is different but all out performance you look at power under the curve in its powerband which is really 6-6.5k to 8400.
Higher revs does not increase performance because you can stay in the revs for longer as the powerband is simply adjusted quite far to the right in a high-revving car. An F1 car never dips below 17000 RPMS's so its not like the advantage is there because it can sit in second gear from 11k-19k RPMS.
If you compare and bench race a 335, you look at its powerband where its gearing allows it to be during max acceleration which is about 4.5-6.5k RPM's so a span of 2k RPMS roughly. Compare that with the area under the curve of power for the m3 which again is really only a 2k RPM span, so no difference in total number of RPMS available to play with, but rather the effect the RPM's are having on the power output. Within the 6k-8500 RPM range the m3 uses its high-revs coupled to a weaker torque to produce its power which is illustrated by the power curve.
A 335 takes its relatively higher torque (given its power) and uses the lower amount of revs coupled with the higher amount of torque to produce its power curve during those peak 2.5k worth of band. The total area of those 2 curves (power curves) is indicitive of its maximum output during its powerband during maximum acceleration.
Go to youtube and watch an all-out sprint with someone video taping the RPMS's and you notice when all-out a 335 never dips below 4500-5k rpms and the m3 never below 5500-6k. They both only have about 2k-2.5k worth of RPMS to rev through so the m3 is not using more revs to stay in the band longer.