5.0 swap fuel pump

[Stvstr]

I have a stock 92 Mustang 5.0 in my 1988 325is and connected the fuel lines as per the e30V8 manual. It idles perfectly and up to about 1/3 throttle and under 2500 rpm runs as expected. Under more load, though, it sputters and misfires and will not accelerate. If I back off the throttle it returns immediately to running correctly.

I checked over the ignition wiring, timing and ground leads and it all looks fine.

Does anyone know if the in-tank e30 pump is enough to run the 5.0?

Thanks

[teamols]

maybe

I am not sure but maybe Google fuel volume and pressure numbers for both

[89 5.0]

Im running 24lb injectors with the stock single late model e30 pump and no issues at all. Should be enough flow up to ~300hp

[eurotrash]

Intank wouldnt be an issue as thats just there to keep the external pump from cavitating. I'd try upgrading the external pump and running an adjustible fpr with a pressure gauge so you can see what its doing. My setup was carbed so i dont know the ford efi real well but i'd think its more of a tps issue or a bad signal from the maf or something.

[e30_302]

Any clogs in the fuel system? Filter, pickup screen, lines?

[Stvstr]

Im running 24lb injectors with the stock single late model e30 pump and no issues at all. Should be enough flow up to ~300hp

Thanks, thats good info as I also have the same single intank pump and a stock 5.0. Drove it more yesterday and under any load more than 1/3 throttle it will accelerate normally to 2 -2500 rpm then sputter and misfire and stop accelerating. If I back off the throttle it immediately resumes running smoothly, but generally will also backfire out the exhaust at the same time.

I am assuming the backfires indicate the exhaust is loading up with unburnt fuel when its misfiring, which then ignites when I back off the throttle and it resumes running properly. That makes me think it's an ignition problem, not a fuel supply problem, so I will look over my ignition system again. But I'm an amateur mechanic, anybody have anything to add?

Otherwise I love the low end torque and the car doesn't feel heavier than with the m20.