Are you the proud owner of a 1994-1998 12 valve Cummins? If so, you own one of the most proven, longest lasting diesel engines ever produced! So why would you want to mess with perfection? The reason is simple...that neighbor of yours just bought a brand new diesel that comes from the factory with 150 more horsepower than your truck came with. But that's not the only reason, a 12 valve Cummins has the ability to be ...