The results are in! The fuel pump relay did the trick and A/F is holding rock solid now. The car was running pig rich when they put it back on the dyno so the wiring obviously made quite a difference. Final numbers: 487 whp and 465 lb ft at just over 10 psi tapering to ~7.5 psi. Dat torque. It's pretty damn cold out right now so traction is severely limited. Having said that, the car feels like an absolute monster. 3rd gear is insane
The shop is going to send me an overlay of the baseline and final runs tomorrow but for now here's the final run. Baseline by itself is in the first post.