If an engine with high horsepower can gear down to increase torque, couldn’t a high-torque engine be geared up to increase horsepower?

Question

Just wondering why, in these discussions, people always say the former and not the latter.

In: Engineering

Answer 1

Torque and horsepower are not the same thing and the terms are not interchangeable. Horsepower is the product of torque and speed and remains constant (simplifying a bit). If you increase the torque, the speed drops and if you drop the torque, the speed increases. The product will remain constant.