Just got home from the dyno and another disappointing day I think. We were shooting for 500+ with 20psi but couldn't get the fuel to flow and it would drop off at the end. So at the end of the day we were only able to run 18psi up to 6500rpms, got 427rwhp. Power would have kept on rising if we would have went up to 8000rpms but the damn fuel

Here's the setup. The intank is a Bosch Supra pump. From what I've read it's the badest intank. On top of that we have a Vortec T-Rex inline pump. This should be good for at least 500 if not 600. We measured pressures at the fpr and right after the pumps. Both were dropping so that tells me it's coming from the pumps themselves.

Any ideas anyone? Ralph, the tuners says it might be the intank pump's outlet hole. It could be too small and not letting the flow out like it should. The T-Rex pump is good for sure. These are the pumps he uses inline for 500whp hondas

 

Next time, measure voltage at the pumps under heavy load. Voltage drops have been known to happen when high currents are drawn through the stock fuel pump harness.

If it's the intank pump outlet that's too small, put a catch tank between the pumps.