GT 3000 VR-4 tuning?

[Shane@DBPerformance]

Some people run 550s with an SAFC, I wouldn't run over 450s with one though. 3S's run too much timing past 5500 RPMs at higher boost on pump gas and are pron to knock. With bigger injectors than you need, you need to go farther negative on the SAFC, which has the side effect of making it run more ignition timing.

The MAFT Pro can retard ignition timing on those cars and tune fuel or the E-Manage systems are popular options. An AEM FIC might work also, but the built in MAP sensor on that box is only good to 22psi(can be upgraded though).