compression release engine brake (jake brake)
Posted: Wed Dec 14, 2011 3:54 pmjust thought this website would help a little bit when or if you get around to adding diesel engines http://en.wikipedia.org/wiki/Jake_brake 
Just a thought,
You really couldn't put a Jacobs Brake(Jake Brake) in a car the compression would be so strong when you hit the Jake Brake the car would skid.
Not unless you make an pick up with it or a very very heavy vehicle.