[richard in NC]

Originally Posted by Dr Stig 2

Therefore almost all cars have a fairly linear power curve from about 1000 rpm to the peak.

When the Torque peak starts to fall off, you get a boost from the higher power levels in the driving acceleration, as you are burning an incredible amount of fuel from 5000rpm to 6500rpm which is converted to kinetic energy.

Many race drivers will ignore the power peak in a good turbo car, where the torque figures are huge in comparison to the normally asperated cars.
They will drive in the 2000-5000rpm band and use the torque for everything.
They miss out on the high screaming noise of the top rpm in the engine range, but they use less fuel for the endurance aspect of a race and miss out very little on accelerative force and acceleration times.

It is correct that the torque curve is more important for daily driving and HP is important for racing because they do stay in the high HP ranges all the time.

I agree with everything stated except the quoted statements. Because the HP is a function of torque x RPM, the slope of the HP curve matches the torque curve. It is only linear if the torque curve is not a curve (ie flat).

I also disagree with getting an acceleration boost at high RPM. The acceleration rate matches the torque curve only. In the M5 V10 you would feel a high RPM boost but only because the torque curve rises in the 5000-6000 RPM range. It would not be the case in the 35i with its flat torque curve.

Lastly, I'd bet the turbo cars have a lower torque peak, and likely RPM peak than the NA cars.