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 ...

I'm wondering what kind of mathematical models there are for estimating engine performance.<BR><BR>Say you want to model the performance of 1.2L tdi VW engine or a 1.3L fiat/gm engine in a car with a ...

My friends Volkswagen Tiguan 2.0 Auto Diesel does 60mph at 2000 rpm in top gear on a flat road. I think this is about 500rpm too much. There is no change in rpm when switching the gear change from ...

If you’re new to the off-road world or unfamiliar with the way the axles on your truck work, then you might be unfamiliar with why you’d want to bother changing the gear ratios in your truck’s axles.