Building your 4x4 can be one of the most enjoyable and rewarding adventures that you will ever take. While we understand that not everyone is a master fabricator, simply getting to know the basics of ...

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 ...

Differences in the track, tire sizes, class rules, and other factors can cause you to rethink your selection of gears, possibly from week to week and even from the beginning to the end of an event (in ...

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, ...

The axle connects two or more of a vehicle's wheels to the same axis, whether on the front or back, and depending on how it's configured, the performance of your ride can vary greatly. Furthermore, ...

The optimal gear ratio depends on how the engine fits the intended use of the boat. Courtesy Yamaha In every boat test we run, we include certain specs that we feel are valuable to our readers. Some ...

What's the deal with the Jeep Wrangler Rubicon's four-to-one (4:1) transfer case? What about those 4.10 gears in those beefy Dana 44 axles? Why is it that when people put bigger tires on their ...

From a load-capacity point of view, the most suitable gearhead ratio has the highest torque density for the most compact (and cost-effective) package. From an application point of view, the best ...