So I can't for the life of me, figure this out.


I installed my Radium surge tank with AEM 320lph pump, Radium Fuel Rail, and ID1000 injectors. When I start the car, my fuel pressure at the rail is at 90 psi. I drilled the return orifice to 3/32 and removed the filter, and it only dropped to 86 psi at the rail. I'm still on OEM FPR.

 

Why did you spend all that money and then cheap out on the FPR?

 

Well I was looking at razorlab's build, and he was running the oem FPR on a Wally 450 and pump controller. I guess I was hoping with only a 320lph pump, I could get away with it. Anyways, I ordered the MAP AFPR kit so hopefully I can have it fixed before the weekend and start tuning.

 

I think its the most likely cause, the oem diaphram cant hold the output of the pump, therefore its pretty high, aftermarket should fix it, either that, or your fpr is bad, which i doubt lol