The 351 Cleveland in my '72 Ford Gran Torino needs a rebuild. I recently bought a '93 Thunderbird for the AOD and EFI and I have a GT40p 5.0 out of an Explorer. My plan is to pull the Cleveland and FMX and put in the 5.0 and AOD. The EFI needs a lot more fuel pressure. I can use the existing fuel line from the tank as the supply, but I need a return line. The tank may have a vent I could use, but I was thinking..
The EFI pump would be external and would go back near the tank. Adding a tee between the pump and tank then running the return back from the fuel rail to the tee seems like an easy solution. I'd still have the open vent and wouldn't have to modify the tank. Am I missing something? Seems too easy. Thoughts?
lrrs
HalfDork
2/2/20 7:32 p.m.
That will work, but it's a pain to get the air out of the system.
I ran my subie swapped bettle kit car this way for 3 years until the chinesium fuel pump died. Ran a return when I replaced the pump as I did not want to spend the time trying to purge the air out again.
Vigo
MegaDork
2/2/20 9:31 p.m.
Downside of that setup is you will heat the crap out of the fuel since you won't be recirculating much of the total volume. It may be a minor factor and have no real downsides, but I'd honestly just buy 15' of low-pressure fuel hose and zip tie it all the way back there and have a real return line. ~$20
The problem I see with the Tee idea is that you get rising fuel temperature in low load situations. The returning fuel has already been in a hot engine compartment and should go back into the tank to cool down. Just add a fitting somewhere above the fuel level in the tank. If the gauge sender is on the top that would be easiest, but I know some Fords are not so located. Otherwise put it in the filler neck, use a bulkhead fitting with neoprene O rings.
