My Take On Torque

I dropped out of college 'cause I didn't have the brainpower. That may explain why I have so much trouble understanding why torque numbers have such a big place in the advertising of personal vehicles. Semi rigs don't boast about torque, nor do large farm tractors - all they care about is horsepower. To further complicate matters, one can have torque without work and one can have work without torque.

In days past, I guess it was meaningful to know your diesel pickup had exceptional low end torque. This meant you could let the clutch out at idle and pull your boat up the ramp. With a similar gasoline powered pickup, you'd have to rev the engine to get her up in the torque curve and feather the clutch or the motor would lug and die. But things are different today because we have sturdy automatic transmissions which take the guesswork our of how many RPM's we'll need to get the work done and there's no clutch to feather, so what do I really care about where/how torque comes into play?

There's an article at How Stuff Works that says a gas motor can match the torque of a similar horsepower diesel motor by the use of gearing. To me, this suggests that torque is more a product of mechanics than the ultimate ability to get work done.

So here's how it makes sense to me:
Horsepower does the work. If you want to do more work or faster work you'll need more horsepower.

Torque is the potential ability to accelerate. Where the big torque numbers show up on the RPM curve, that's where you have the ability to take on the most work. In the case of the diesel, it's at a low RPM. In the case of a gas motor, it's near the top of the rpm range. But with the proper gearing either will produce the same amount of torque, just at different RPM's. If you want to have more torque without gearing you add horsepower.

Let's say our car is jet powered - no torque involved at all. How do I make it go faster? Yup, by increasing horsepower.


So like I said, it appears to me that if you want to do more work or do it faster, you add horses.