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      01-03-2013, 06:07 PM   #9
MKE_M3
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Drives: 2011 e90 M3
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There are engineering advantages (and some disadvantages, of course) to generating horse power at high RPMs, vs. low RPMs.

Consider two engines, both putting out 414HP, one puts it out at 8000RPM, the other at 4000RPM (think big turbo diesel). The first only makes around 250 lb-ft of torque, while the second makes around 546 lb-ft of torque. The drive train strength for the car making 250 ft-lbs is much lower than the needs of the engine producing 546 ft-lbs. This means that the high revving engine can be partnered with a lighter drive train. Additionally, less torque requires(generally) less displacement (or lack of hardware like super/turbo charger), which also saves weight.

Lighter is better for sports cars.

Additionally, there are gearing advantages to high revving engines, the car revving to 8000 RPM can get twice the mechanical advantage (half as tall of gears) as the low revving engine while covering the same speed in each gear.

Lower gearing is better for sports cars.

So if you like light cars that are aided by mechanical advantage, then high revving is for you

The main downside is obviously driveability, which is not a high priority for sports cars.

To determine what is more important to you, consider this.... would you rather drive an NSX to the local grocery store, or a turbo diesel truck cross country?
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Last edited by MKE_M3; 01-03-2013 at 06:35 PM..
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