Here is the problem. Under boost say over 15lbs, my fuel pressure strarts to drop down to around 40psi. Im going off my KB hood mount gauge. I have a 340 Walbro maybe like 1-2 years old (bought it new) with a hotwire kit. Also run 60lb injectors with a PTDBB 61 turbo. Have a Extreme Extender chip also if that matters. Heres what I have tested so far.
I checked the adjustable fuel pressure regulator. With the hose off is at 48psi and when I use a vacuum pump and run 15" of vac, the feul pressure drops. At idle when I increase pressure with a pump at the fuel press. reg to say 15-20psi, the fuel pressure increases that amount and it doesnt dropp off if I hold it there. Also checked for power. Found with the car running and under boost Im still seeing 13.5-14v @ the alternator and the same voltage at the wire right before the fuel pump near the tank. So I think I ve eliminated a "wire/power" problem and the regulator seems to work fine. Could it be the fuel pump that is bad? And which fuel pump should I go with? I plan eventaully to run in the low 10's. Also fule filter was changed less than a year ago. Thanks!
I checked the adjustable fuel pressure regulator. With the hose off is at 48psi and when I use a vacuum pump and run 15" of vac, the feul pressure drops. At idle when I increase pressure with a pump at the fuel press. reg to say 15-20psi, the fuel pressure increases that amount and it doesnt dropp off if I hold it there. Also checked for power. Found with the car running and under boost Im still seeing 13.5-14v @ the alternator and the same voltage at the wire right before the fuel pump near the tank. So I think I ve eliminated a "wire/power" problem and the regulator seems to work fine. Could it be the fuel pump that is bad? And which fuel pump should I go with? I plan eventaully to run in the low 10's. Also fule filter was changed less than a year ago. Thanks!