What you mentioned is correlation,

that higher-hp cars tend to have higher over-all acceleration performance. But correlation doesn't imply causality. Causality is what hp-related marketing is implying, that high hp is what causes better acceleration. What I demonstrated is that it is the torque curve together with gearing that is the causality for acceleration. Most of the time, engines that have good overall torque and can support high gear ratios tend to produce high hp numbers as well, that's where the correlation you see comes from. But for any specific car's performance, correlation with hp doesn't give you 0-60 times, integrating out my ODE with the torque curve does, because that equation is the causality. Let's do another thought experiment, where you have two 200hp engines, one with flat torque from 2000 to 5000 rpm, the other has slowly increasing torque with a single peak at 6000 rpm. The first engine will do a faster 0-60, with optimal gearing for both.

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• 回复：What you mentioned is correlation, -kfbai- ♀ (975 bytes) () 12/07/2005 postreply 17:34:42