EFI conversion

Anybody here done an EFI retrofit/conversion? I'm wondering about the return line. Curious to hear if you used the vapor canister line as a return, or soldered in a fitting at the sending unit. There doesn't seem to be a sending unit for '71-3s that has a return line already installed.

On my 65 I ran a new dedicated fuel feed line, and used the old fuel line as the return. A local radiator shop welded a firring into the tank for the return fitting.

This past weekend while working under the hood of the 73 I looked at the vapor retun line, and thought it would make a good main fuel line, thinking the larger diameter would be more useful as main feed rather than return.

One feature I may have differen on my EFI is a "header tank", this is a small(roughly 1.5 quart size) that is fed by a lowpressure pump, then the High Press EFI pump is in the header tank. This is used instead of trying to devise baffels and a main tank EFI pump.

Check for info on the header tank

I believe you can now but tanks already set up for EFI:

http://www.glennsperformance.com/index.php?cPath=78

Wow, $400 for a tank . . . and I put a repop tank in just a few years ago. I think I'll just get a repop sending unit and braise a second fitting into it. My pump is going to be inline.

Wow, $400 for a tank . . . and I put a repop tank in just a few years ago. I think I'll just get a repop sending unit and braise a second fitting into it. My pump is going to be inline.

Click to expand...

I ran a projection for a while. I drilled a hole in the sending unit and used... get this... jb weld. Worked like a champ. In fact, the fitting is still there but I have since moved away from the fuel injection.

One problem I had was the original tank isn't set up for fuel injection. If I was down to 1/4 tank or less I would lose fuel at the pickup when taking left turns (especially long turns on freeways at speed and such). Not a problem for a carb car since it has fuel in the bowls but a FI car needs constant gas and pressure. I was always worried I would melt a piston.

I used a new stock tank and had a -6 flare fitting welded onto the top. I also had a sump welded to the bottom to keep the inline pump gravity fed.