ELI5: What people mean when they say a car has lb-ft of torque.

A lot of people are saying that torque means acceleration, and that's totally bullshit. Almost any car has enough torque in first gear to spin the wheels out, and once you start shifting up it means the engine has hit maximum power and are limited by that.

If you have two engines with the same horsepower but one has half as much torque, that just means it spins twice as fast and if the car is properly designed the gear ratios will be twice as high and it will drive exactly the same.

The way torque does affect driving is the torque curve. This is a graph of how much torque the engine produces with the throttle 100% open at every RPM. On some engines you only get peak torque at really high RPM, so it's not even something you'd notice unless you're driving really aggressively. A lot of modern engines, though, achieve near maximum torque around 2000-2500 RPM and it's roughly constant up to redline. Those cars are much easier and more pleasant to drive. (Though with an automatic transmission you wouldn't notice that much.)

/r/explainlikeimfive Thread Parent