If you know engines, then you’ve probably heard of the 2.7L and 3.0L Pontiac Super Duty four-cylinder engines. The SD4 was never available in a GM vehicle, but you could order the parts to build one through your local Pontiac dealership. This hot-rodded version makes an estimated 100hp per cylinder. Want to hear it run? Check the video online at jpmagazine.com/prine_pt2.