My camaro had almost the exact same set up his car has. I had an ms3, PRC stage 2.5 5.3 heads, pace setter Lt's and ORY, SLP lid, Ls6 intake, ported maf and tb and a flowmaster and my car made 439/398. Both of our cars were tuned by brian and on his dyno. When i swapped to a bullet off of the ORY and had it back on the dyno there were no gains for me.