HP vs Torque
For the horsepower does not matter it is torque that accelerates debate. Video
Forum Discussion
Basically, you need torque to overcome the resistant forces of the load in order to move it and the amount of horsepower you are making determines how fast you can move the load. It is not about peak horsepower and more about the amount of horsepower you are making at the engine speed where you are applying enough torque to keep the load moving.
If the resistant forces increases(i.e. going up hill) and you do not have enough torque to the wheels to overcome the increased resistance. Then your vehicle will downshift to multiply engine torque to a point where it has enough torque to the wheels to move the load, and your road speed will be determined by how much horsepower you have at this engine speed.
Where it gets tricky is with an automatic transmission. If the torque converter is not locked then it is multiplying torque, but it is not sending all of the engine's horsepower to the wheels. So in many wide open throttle situations at high engine speeds, you are not sending all of the engines horsepower to the wheels and instead it is just wasted spinning the torque converter to multiply torque.
If the resistant forces increases(i.e. going up hill) and you do not have enough torque to the wheels to overcome the increased resistance. Then your vehicle will downshift to multiply engine torque to a point where it has enough torque to the wheels to move the load, and your road speed will be determined by how much horsepower you have at this engine speed.
Where it gets tricky is with an automatic transmission. If the torque converter is not locked then it is multiplying torque, but it is not sending all of the engine's horsepower to the wheels. So in many wide open throttle situations at high engine speeds, you are not sending all of the engines horsepower to the wheels and instead it is just wasted spinning the torque converter to multiply torque.
