Recently changed in-tank pumps due to my Aeromotive A1000 starving the pick-up at low volumes. Went with a Bosch pump.
I have 44.5 # injectors, Fast rails and run 58psi.
Now with new pump at 3/4 throttle, accelerating I get a brief pressure drop from 58psi to 52psi. The motor doesn't nose over, I can't tell that it affects it at all. It is a parallel set-up with the regulator behind the injectors.
Should I be concerned? Is this a tuning fix?
My Aeromotive stayed rock solid at 58psi, but it moved alot of fuel.
If the pressure drops, the car goes lean unless it was [not the right way to do it] tuned around the pressure drop from the beginning. If it was tuned at a stable 58psi though and it falls now, then the car is leaning out. The PCM cannot see fuel pressure and at heavy to WOT cannot make correction.
Great, have a modified Ricks mini tub tank which we added extra baffle doors to help with slosh. Recently switched pumps as stated above.
It is a custom parrallel feed/return line set-up. Y block split into two lines that feed the FAST High Flow rails with a Weldon regulator on the return side, I don't think it has a vaccum line- I'll look tonight. Bosch 44.5# injectors.
With the Aeromotive pump I never had fluctuations upon acceleration, but with low fuel volumes in tank and when cornering (slosh) it would starve the pick-up. At fuller tank volumes- no problems. Rock steady pressures. Switched pumps thinking that the Aeromotive was moving alot of fuel so fast that at low volumes it would starve at the pick-up.
Switched pumps and now on 3/4 throttle acceleration I'll get a brief, maybe 1-2 maybe 3second drop in pressure from 58psi to 53 or 52psi, then it recovers.
Thanks for any input.