[Shane@DBPerformance]

Diesels are usually for gas mileage or pulling. You usually pull best with torque, you make more torque at lower rpms. You get better gas mileage at low rpms too. They are usually heavy rotating assembly motors, built to run very high boost to make high torque at low rpms and get gas mileage while doing it and not built to spin high rpms. Pro diesel tractor pullers might see RPMs in excess of 6000 though, but they aren't exactly a street truck/car made to last forever and save gas.