At nearly 30 feet long with a 1,500-hp Caterpillar engine behind the cab, The Prospector is cool even when it's sitting still ...

Find out how much horsepower a semi truck really has—from 400HP workhorses to 730HP European beasts. Plus, why torque matters ...

The massive RC Audi boasts a custom-made clutch disc and pressure plate, axles, differential, brakes, and an engine that ...