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 ...

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, ...

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 ...

Even good cars only give the driver two speeds to monitor: engine speed and vehicle speed. And while it’s the engine that ultimately does the work to turn the wheels and move a vehicle, a lot goes on ...

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 ...