Fuel system change from FiTech to stock


New Member
Sep 7, 2021
Lafayette, LA
Hey there guys (and gals),

I have a 1965 mustang with a 302 out of a 1989 fox body in it. Long story short, I stroked it to a 347, put AFR 165 heads, and a Howard's cam in it and pulled 451 hp on the engine dyno. That was on a carb. I get the engine in my car, and hook up my FiTech. It's the goefi 4 master kit https://www.jegs.com/i/FITech-Fuel-Injection/546/31002/10002/-1 and I've been having issues with it non stop. I have disabled PWM for the pump (it's inline) and can't use timing control with my specific distributor. The ECU has burned out because of a design flaw of theirs and I'm just done with this crap. Not to mention, my engine is ready for boost and I can't because of this FiTech. I have a friend with a 1989 crown vic with the 302 in it and I want to use all the factory fuel parts on the engine side, run this Ron Francis harness, and this holley fuel pump setup (with the upgraded 315 liter pump of course). I have the harness, and the donor car readily available, I just don't know what y'all think about the stock ECU. I only plan on running 8 lbs of boost, but I know it's the EPROM style ECU. Am I being irrational here? Realistically, how hard would this swap be? How do I go about getting the tuning done so the ECU see's a 347 with 8lbs of boost?
Thanks for the help.


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Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
I second the megasquirt for your combo. The factory computers are getting old and having their own set of issues. You'd have to source a mustang computer to run the 347 and use a chip to tune it. In the long run the megasquirt ecu would be more cost effective.
  • Agree
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