Finally got around to doing my 3 1/2" downpipe/4" straight pipe exhaust on Friday, put the 366 governor spring in this afternoon. I was able to have my fuel screw at the same position, not sure about the idle screw, lost track. It feels a little stronger and certainly revs faster and pulls to 3K, but kind of runs out of breath above 2500 RPM. The boost doesn't drop off though so I know its not defueling. EGT's are a little higher and boost is down 3 psi, but its a very hot day today, probably 20deg warmer than when I took the truck out w/ just the exhaust. I'd imagine if I didn't have stock injectors and turbo I'd notice more of a difference and it would pull harder at higher RPM. -Nick