fuel pressure reg question

[250zt]

Having trouble getting my rb25det running right. It starts and runs, but it runs very rich. Computer shoots no bad codes, afm, throttle position, and water temp sensors all check out. Computer appears to be stock nissan as do the injectors (dark blue color). The fuel return line is new and not blocked. I put a short hose from the return line into a can and ran the engine for about 3-5 seconds and it pumped about 2 cups of gas into the can, so i'm guessing the fuel pressure regulator is doing all it can to keep up, but im still running anywhere from 46-52 psi fuel pressure. I have an aeromotive pump good for 450 lbs/hr. at 45psi and 65 psi max pressure. Is this too much for the stock pressure regulator? If so, any suggestions for aftermarket/upgraded regulators? If not, any idea why my poor rb runs so crappy? The engine is from an r33 skyline gts-t and its in a 1971 240Z.

[Andrew85cm]

Phase2motortrend sells adjustable fuel pressure regulator for the RB motors. Well its nonspecific but it fits. It's a Nismo one or something they cost about 125 dollars. You really need one thats a good bit of fuel pressure over stock. I think I got the type B for my RB20det so if you do a quick search you can find out if they are the same.~ANDREW~