Originally Posted by
rydabent
Power or horsepower that everyone talks about is basically torque over a period of time. Torque is the thing that actually moves bikes, cars etc. Thats why trucks are tuned for max torque rather than max horsepower.
Trucks are tuned for max torque at low RPMs because that means fewer engine cycles for a given amount of power, which means better fuel economy and longer service life. Race cars have high horsepower and high RPMs because fuel economy and engine longevity are not a priority, but maximum power to weight ratio is. A large truck engine producing 800ft-lbs of torque at 2,000rpm is effectively producing the same motivational power as a small sports car engine making 200ft-lbs of torque at 8,000rpm. The gearing is all that's different.