Is the stock PCM programming is adequate for long tube headers? I currently have stock programming… minus deleting rear o2’s, emissions, fans to come on earlier, increased rev limit, ext. Basically, I’m wondering if I should send it in to get a performance tune done or would I be better off waiting until I install a cam? Is there much to be gained?



Pacesetter Long Tubes, LT4 KM, Magnaflow Muffler, !cats, !AIR, !EGR, 160 t-stat

 

You can pick up 10+ HP on a stock engine simply by leaning out the PE mode target A/F ratio. So a "tune" makes sense even without the header install. If you had all the other changes made, why didn't they just complete the job and lean it out? Or did you make the previous changes yourself?

Stock tune is "adequate" for the header install, in that its probably no more inadequate than it already was for the stock exhaust system.