Fuel pressure..with 42# injectors....??

Rock777

Member
Aug 22, 2004
195
1
16
Troy, IL
My buddy just bought a car. It is has edelbrock alum. heads, GT40 intake, E cam and all the bolt-ons. Anyway, the guy he bought the car from had it supercharged before, hence the 42# fuel injectors. I just wanted to hear some ideas for ballpark estimates of what the fp should be set on. Believe it or not, right now he is running the stock fuel pressure regulator and with the vacuum off the pressure is at 45# :jaw: , so you can imagine how rich it is running. I realize that 24#'ers would be optimal, but I am thinking the pressure once he gets an AFPR on should be set around 32-34 with the vacuum off. Does this seem right? Anyone have any ideas?
 
The fuel injectors were designed to be run at stock fuel pressures. If he's too rich then there are a couple of things that can be done. He can get a cutome tune or an ECU tuner to modify the injector pulse width or attempt to recalibrate his meter. The stock EEC program has the wrong minimum and maximum injector pulse width settings (wrong ramp setting as well) for 42s so a custom chip would be the preferred fix.