My motor runs really hard in open loop, as soon as it goes into closed loop it is really FLAT! So basically my car is fun to drive for all of 90 seconds. It drives pretty smooth but when I put my foot down it just dosen't pull? All new tune up parts and O2, and I just put in a 255 fuel pump 2 days ago, no change? I just feel like I'm missing something, probably something very stupid! Anyone have any idea's?

Thanks in advance

350, 9.77 comp, CC306 cam 230/244 .544/.566 with 1.6R.R.'s, T-5, 3.73 gears,Holley Stealth Ram, AFR 195's, 30#SVO injectors, SLP shorty's, 3in. exhaust with no cat. Tuned 3 times by PCMforless