I'll try and beat Bob off the line here... it's rear-wheel torque that
pulls you off the line, and engine power, not engine torque alone,
actually determines how much rear-wheel torque you can generate. If you
have 1800 engine RPM and you're putting it through a total reduction of
say 6:1, you'll get 300 rear-wheel RPM, which you can translate to a
given speed. The 313 foot-pounds of torque at the engine translates to
1878 foot-pounds at the rear axle (neglecting for the moment the
drivetrain losses). The same 313 foot pounds of flywheel torque at 3600
RPM, which amounts to double the power, can be run through a 12:1 gear
reduction to give you 300 rear-wheel RPM and 3756 foot-pounds at the
rear axle. Double the power equals double the torque available at the
rear axle.
Being able to use the engine's torque curve to advantage still applies.
If you're mostly doing street driving, you want an engine that's not
tuned to operate efficiently over just a very narrow powerband, which is
what you've done, but for outright acceleration, generating the most
power for the longest amount of time is what you need.
Best regards,
Theo
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