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Old 02-14-2015, 07:27 PM
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Quote:
Originally Posted by Grubby View Post
An engine build can be tailored to have a lot of torque or a lot of HP. There are always trade offs. Typically high HP would be made at higher RPMs and less driveability.

What do the engine builders have to say on the subject?

In a light weight Cobra, would you aim for HP and torque numbers to be similar or would you push for torque to be much higher than HP.

For example in a street driven Cobra would you prefer;
520 hp at 6000rpm and 540 torque at 4500rpm or
450 hp at 5200rpm and 570 torque at 4500rpm.

What is your logic behind your opinion?

John
John,

All engines produce the same numbers at 5252 rpm, because it is a constant in the HP/torque equation.

HP=Torque x RPM / 5252

So in your examples above, the second of the two has a torque curve falling flat on it's face, only 700 rpm past it's peak.

570 ft/lbs at 4500, falling over to 454.5 ft/lbs at 5200.

Out of your 2 examples, the small difference in the 2 torque peaks is offset by the 1st example making 455.1 ft/lbs at 6000 rpm.

It all depends on what the owner wants.
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