You're driving a loaded diesel rig down a mountain pass, foot hovering over the brake pedal, heart racing. How do you slow 20,000 pounds safely without cooking your brakes? Cue the exhaust brake -– ...

If there's one question that's forever on the lips of car enthusiasts, it's how much horsepower an engine makes. Answering that question is deceptively complicated, however, because of what the term ...