I have a Kenne Bell 2.1 with a BAP and a 255 Fuel pump. My car is a 97 GT and I have a P.M.S. installed as well. My car keeps going fat on fuel at WOT and can't lean it out. Is both the 255 fuel pump and BAP sending to much fuel? I have also been told that the BAP doesnt allow you to do much tuning with fuel at WOT. Any help would be great.
Do you have a fuel pressure reading from the rails? 97s have a return-type fuel system, where the FPR returns "excess" fuel to the tank via a return line. With a 255lph pump and a BAP I'd think you've got plenty of supply but if the return path is restrictive, perhaps the fuel is backing up ahead of the regulator and causing a spike in pressure in the rails.
First...pick yourself up an adjustable fuel pressure regulator to rule out the posibility that your stock non adjustable unit isn't going south. Second....dump the "HOBS" switch that comes with the BAP and just wire it up direct. When I had my car done, my tuner stated that he had a tool box full of them. The HOBS switch comes on (at I think 3-5psi as standard) and "spikes" the pressure, making it tough to tune. Getting rid of it and wiring it direct won't hurt anything and will keep the fuel flow more consistent. I've been running my car going on 3-years like that with no issues.
