How do you convert engine horsepower to wheel?

Answer 1

There are many variables in this but gererally for an automatic car, there is a 22% loss in power from the engine to the wheels and for a manual about an 18% loss. If you made 250 wheel hp in an automatic car you should be around 305 hp at the engine.

Answer 2

You get the engine horsepower from the manufacturer. They take it off the flywheel. You take wheel horsepower by putting a steel band around the tire. There is a pole attached to the band. The pole extends out a foot or two from the vehicle. A big flat square piece of metal is attached to the end of the pole. That piece of metal is put on a scale. That way a shop figures out wheel horsepower. The conversion shows that about 50% of the power at the flywheel makes it to the wheels. Since electric generators and motors have greater than 90% efficiency, conversion to gasoline-electric vehicles could theoretically double mileage.