Hi guys , need some help in diagnosing a fuel pressure problem.
Its is not an efi car. Here gos smallblock chev 355, BG750, areomotive pump (efi) with return port, 1/2" fuel line,-8 return. If the car is off and pump running there is no pressure loss (8psi) and stable. when the car is running and warm the pressure drops to ( 2psi). Tried new regulator, new pump, new filter, there also proper voltage at the pump. This is not my car but a freinds,no one including areomotive tech can solve. Any ideas would be appreciated greatly, the only thing i can think of is to big a return line,and bleeding pressure if Im wrong please let me know
thanks in advanced!