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Old 10-04-2011, 02:43 AM   #16 (permalink)
tjts1
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Quote:
Originally Posted by Patrick View Post
Power remains the same, but RPM is lower, therefore torque must be higher, requiring a larger throttle opening.
No, with taller gearing for a given road speed, you still need the same amount of air to send the same amount of torque to the wheels. RPM decreases, absolute manifold pressure increases, throttle angle remains the same, torque remains the same. On a naturally aspirated engine you reach you peak torque for a given RPM when manifold pressure is at 100kpa regardless of the throttle angle. At low RPMs you can reach peak torque at 30-50% throttle.

Last edited by tjts1; 10-04-2011 at 03:12 AM..
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