Too much fuel pressure?
 

I have an 02 Silverado with an LQ9 swap. I recently installed a TBSS intake and used the C5 vette filter so I could keep the fuel return line. I also installed a Racetronix 255 LS1 pump. But now I am seeing 74psi at idle. It's about 58psi with just the key on and fuel pump pressurized, which is what the vette filter is supposed to regulate the pressure too. I checked the return line for kinks but found none. I removed the bucket to check the return thru it and everything seems fine. What gives here? Is the fuel pump over powering the vette filter? I wouldnt think so, there are plenty of walbro 255 pumps pushing thru the vette filter with no issues. Is my return line too small? If I leave it as is, what problems will the high fuel pressure cause in the future?

Yeah, that's too high of pressure.

It'll idle rich and be rich everywhere else because the add pressure will push more fuel out of the injector each time it fires.

Maybe it's a bad filter?

I'd rather run a separate regulator myself, seems easier that way.

I tried 2 different filters but both a Wix and the Ac Delco read the same pressure. I was hoping the wix had a bad regulator but that wasnt the case.

So I began looking for restriction in the fuel return line. Visually I dont see anything kinked or crushed so I removed the return line right at the tank and ran that line to a gas can. Started the motor and still had 70 or so psi. I also had what seemed like alot of fuel in the can so I thought the return line was flowing good. Next I removed the return line right at the vette filter return port. I clamped a 3 foot section of 5/16 fuel line to the return port on the filter and ran that to a gas can. Started the truck and I now have the correct 58psi at the fuel rail. I highly assume I have a restriction in the return line somewhere but I just cannot trace it down! Can someone tell me what braided line along with quick disconnect fittings I need to run a new return line. I figure staying with the 5/16 diameter should be fine? Thanks for any help!!