In a diesel engine, adding more fuel will almost always result in more horsepower, and last month, that's exactly what we did in our "Fuel It Up!" article. There are drawbacks to making power in this ...

Almost nothing can beat compound turbos in performance applications. While a big single can make plenty of power, compounds will spool quicker, tow better, be more driveable, and are capable of ...

This file type includes high resolution graphics and schematics when applicable. The images above are simple cross sections of a typical spool valve (left) and a poppet valve (right). (Courtesy of ...