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 ...

What if-and believe me, this is a hypothetical-you were trying to put a wild, rare, 200-hp naturally aspirated Autech SR20DE from the hottest of the nonturbo S15 Silvias into a first-generation Miata, ...

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, ...

For part two of our series about transforming Jared Lehenbauer’s new-to-him ’01 Ford F-250 into a truck that’s better suited to his needs, we’re detailing how to select the correct gear ratio for two- ...

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 ...