A chip programmer will boost HP by as much a 50% on these super powerful machines. The additional 5” exhaust stack will also let the engine breathe better, but very little expense is needed to make them howl like a banshee. Performance is built into them. In fact, the factory puts rev limiters and detunes them to hold them to a mere 325 HP. They are capable of much more than that by simply changing the computer program.
I have a 2001 Excursion with the 7.3 Powerstroke and an older (2002) Superchips microtuner, but I can’t get near the 450 hp mark. But then again, with 212K miles on her, I don’t want to kill the transmission :)
Smoke em if ya got em....