Discussion Starter · #1 ·
I have a 98 12 valve last when I started building the motor I started with Afc live(no max travel spring), valve springs and 4k Gov springs. everything was fine at that point. Then once I did 5x14 injectors, T3 3 piece manifold, and a 63/68/.83 turbo, if i free rev it or full throttle in 1st and sometimes 2nd it would almost backfire out the exhaust and spit out grayish smoke. Under normal load 3rd through 5th it would drive fine but Exhaust temps would get a little hot under heavy acceleration or large hills. I have ordered the 35-45psi max travel spring from PDD but havent installed yet dues to waiting for a new clutch. I've thrown around lots of ideas like too much fuel(but it doesn't smoke a lot), too much back pressure from the smaller exhaust side, and not enough lift pump pressure but wanted to see if any one else has experienced this or has had any ideas.