[Sapper_M3]

Originally Posted by ersin

Engine torque means nothing for performance. The number that completely trumps peak engine torque is hp to weight ratio. If you want to bring torque into the equation it has to be wheel torque where you take into consideration gearing.

Also note that the single engine torque figure is the peak torque number only at the engine speed (rpm) that gives this figure. At all other rpms the torque is lower depending on the torque curve. For performance you want the engine torque to keep this peak for as wide a range as possible, that is the torque times the range of rpm that it works over, or as they put it, the area under the torque curve. All torque curves are different for different engines and you would need calculus or a computer to figure out the real engine potential. And this can be done if you get the torque figures for the whole rpm range. However, as it turns out, the maximum horsepower IS the area under the torque curve. And this is why horsepower is the more meaningful number.

So, let me repeat this: a single, maximum torque number for an engine in a specific car alone is meaningless as an indication of performance. Horsepower has more meaning in this context and horsepower per weight happens to be one of the best single number indicators of acceleration and speed.


Cheers.

This. I wish everyone on this forum would read this. Peak Power is a fairly meaningful figure to quote without any other knowledge of a car. For one thing, peak power to weight has meaningful and accurate performance correlations.

Peak torque on the other hand means very little because of the effect of gearing. Peak torque to weight means little to nothing, and a peak torque value even with the gearing ratios is fairly meaningless without the torque curve.