This. Pretty much all you need to know about how power is produced for a given engine and in comparing various ways of producing power (through high torque or through high revs).
The S65 is so different because for a high revving engine, peak torque occurs at a relatively low RPM (3900) compared to peak bhp at 8,300+ rpm. That is an rpm power band spread of over 4,400 rpm, which is incredible and only achieved by a few engines in production automotive history.
Compare this to the Voodoo engine in the Shelby GT350, where peak torque is at 4750 rpm and peak bhp is at 7500 rpm (8250 redline). That is a power band spread of 2750. Even assuming you could make the same or more power at 8250 as you could at 7500 rpm, that's still only a spread of 3500 rpm.
Get the M3 tuned, and it is producing peak power at 8600 rpm, resulting in a power band rpm spread of 4600+!!
Quote:
Originally Posted by Stubbie Blue
It's just the way the equation works out:
hp = torque (lb-ft) x rpm / 5252
If an engine produces peak torque below 5252 rpm, the peak hp will be lower than the torque in lb-ft. e.g. most diesels.
If it produces peak torque at or around 5252 rpm, the peak hp will be close to the torque number. Most engines are like this.
If it produces peak torque above 5252 rpm, the peak hp will be higher than the torque number. Usually high-revving, small displacement NA sports cars are like this.
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