HeliChris

I have a 1994 Mustang GT project on-going. Right now motor problems and I believe they are related to the installed injectors. The engine is a .30 over 302 with 351 ported and polished heads per the previous owner. Cam unknown. It has a Trick Flow intake, 75mm BBK Powerplus throttle body, and A1A Mass Air. The injectors installed are red or bright orange and fuel pressure is 40 psi. I believe these are 30lb injectors, yes? I have a set of 19lb injectors and my thinking is the 30's are way too much for this combo. Sound right? Will the 19's be the better choice? Fuel pressure? Thanks for any and all help here. God Bless - Chris

dawson1112

30s are fine as long as you have the correct MAF calibrated for them. What is the problem you are having?

HeliChris

Engine runs badly, loads up, sometimes dies. Any idea if there would be a problem going to the 19's?

dawson1112

That really depends on the MAF , if you go back to 19s then you have to get a stock GT MAF. Kinda seems like your fuel pressure is a bit high, dial it back to 34-35 psi instead of 40. I ran 30lb injectors with my fuel pressure at 34psi and had no problems with the correct MAF in place.

88 orangepeel notch

Also, have you pulled codes, and if so, what are they ?

If no codes are present, then I'd start by looking for a vacuum leak. 85.37% of the time it's the cause of a poor running 5.0. Good luck

HeliChris

Thanks for the info. I'll try dialing back the fuel pressure and see what happens. Not sure on any codes. No check engine light. Is there a way to calibrate/check the calibration on the MAF? The computer has a chip and that's where I was going to see what the chip manufacturer could tell me. Not much time to work as this is the busy flying season. God Bless

HeliChris

Dialed back to 34# and it wouldn't idle. Sounds like a vacuum problem to me. Time to do a lot more digging. Thanks

Chris

dawson1112

If it wont idle at 34 psi do a base idle reset