Vehicle speed (mph), engine speed (rpm), tire diameter (inches), trans gear ratio, and rear axle gear ratio are all interrelated. If you know four out of five of these values, you can determine what ...

"Give me a lever long enough and a fulcrum on which to place it, and I shall move the world." — Archimedes (287- 212 B.C.) On the street, everything is a compromise. Power is now easier to make than ...

We know there are a lot of diesel junkies out there who are into math and physics, so we decided to put a few basic calculations in one place so everybody out there in reader land could have them ...

Transmission makers have to balance vehicle speed and engine power. The choices they make affect everything from shifting ...

Different gears like spur, bevel, worm and wormwheel, rack and pinion, meshed gears, and threaded bars serve various purposes. When selecting a gear system, consider speed, direction, force, space, ...

Few vehicle modifications have as major an impact as changing gear ratios, and it's because your car's gear ratio directly translates to how it delivers power. Think about it: The gear ratio, or how ...