i need advise on what to do.. a few months ago we did some dyno time in the FD and we got the maps on the power FC good up to 14.5 lbs of boost then the car began to run Lean.. we checked the maps and everything was fine. We did another pull to watch the reg and it would go up to 65lbs under load then shutter and drop to 35-40 lbs and when the load was let off the reg would read fine.. my tuner says it could be a bad reg and other builders are telling me it most likely a fuel filter.. the car runs rich in low revs. and lean up top under load.. we want to go back to the dyno but i dont want to spend 180$ on a new regulator when it could be a 20$ filter.. has anyone had this trouble with the Areomotive regulators.. my set up is a walbro 255 pump to 550 primary and 1680 injectors street ported motor with a T61 singe. and input would help

 

did you rewire the fuel pump?

 

yes

 

Are you running 25PSI of boost? That is what you would have to be running for the fuel pressure to reach 65. If you are then a single walbro is not going to get the job done.

Or do you have your base pressure set at 50psi? This is way too high and will cause all kinds of tuning issues. You should have the base pressure set at 40 (with no vacuum) and you should be seeing 55psi of fuel @ 15psi of boost

The walbros have a safety valve that is controlled by a spring, this can get weak over time and cause the fuel to blow by into the tank. Replace the fuel filter first, if that doesn't help then change the pump. The FPR's rarely fail, it is a ball valve, you would have to damage the ball with a piece of debri for it to not function correctly.

 

no were going for 17lbs but im getting the filter checked out on monday. and making sure my pump is wired correctly.. i just want to get this car at full boost before winter.

 

its probably not the filter. The filter was changed just before I sold it. I also was having issues with it leaning out and changed the filter to make sure. never did find the problem...