I need some help with a fuel pressure issue I am having with my car. the car has a whipple, single blade TB, headers etc. the first dyno attempt was with Focus pumps, and everything was fine on the part throttle tuning but when it came time for the WOT pulls the fuel pressure started fluctuating wildly. the high was 75psi and then would immediately drop to 5psi. it was so bad that we had to call it a day. the tuner suggested to go back to stockers and install a BAP. so I bought some pumps and a BAP from him and returned home. installed them and returned only to find the problem still there. we dropped the tank to look for loose hose. when he saw I deleted the PPRV he thought that was it, so he installed 2 PPRV's from some Focus pumps. put it back on the dyno and the fluctuation was gone. at this point I am happy, so I return home. I go to the track to try it out and I pop a fuse going from 2nd to 3rd. I check into it and it was a 20amp BAP, so I replace it with a 40amp and return to the track and the car just doesn't pull like it should on the back half 101mph 1/8 & 123mph 1/4. it did pick up a little mph in the 1/8, but my car with an un-ported eaton would go 124 in the 1/4....but I digress. so I data log the next pass and guess what, the fluctuation is back.
does anyone know what is causing this fluctuation?
and also what system should I do now? GT pumps, Fore hat, new line and dual stock or dual modified FPDM's......or go return style?
does anyone know what is causing this fluctuation?
and also what system should I do now? GT pumps, Fore hat, new line and dual stock or dual modified FPDM's......or go return style?