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japollon
09-26-2017, 05:26 PM
Does anyone know of an externally mounted electric fuel pump that has suction at the inlet? Most externally mounted electric fuel pumps are rotor/vane and considered "pushers" and not "pullers." While it is a simple thing to mount an electric pump below the fuel tank, on our cars the tank outlet is on the top of the tank so pumps cannot be gravity fed.

Thanks for any help. Joel

Big Blocker
09-26-2017, 09:08 PM
All the early Ranger trucks used an external EFI pump. Never needed to "gravity feed" them, they pretty much worked off a siphon effect. There is just enough "pull" to get them primed and then it's all good-to-go from there.

Doc

Jim1855
09-26-2017, 10:32 PM
I have many friends running the Holley Red or Black and other pumps w/o problems. Most are mounted back by the tank and will pull a short distance. Not sure if they'll pull from the motor like a mechanical pump.
Jim

japollon
09-27-2017, 09:29 AM
Hey Jim and Doc, I currently have the Holley blue pump mounted below the tank on the vertical 2x4 frame member just in front of the axle. I'm really tempted just to leave it a see if it works but am also concerned that if I plumb the whole damn thing and it doesn't I'll have to start all over. My motor has a single 4 bbl at the moment but I wanted to leave myself flexibility in the future to run EFI. If not for that, I'd simply use a mechanical fuel pump. Seems to me that some of the early cars used an externally mounted electronic fuel pump and I just wonder how they accomplished that. The alternative is to use an in-tank pump, but I was just trying to go for the more classic look. Help!

Ray
09-27-2017, 10:37 AM
I have a Holley "Blue" mounted to a bracket that I made just froward of the tank.

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As I understand it, the Holley "Blue" is a low pressure pump that does not require a return line to the fuel tank (which is why I'm using it.) It feeds our carb'ed 302 just fine but won't be capable of feeding an EFI system.

Ray

japollon
09-27-2017, 11:16 AM
Hi Ray, I have the Holley "Blue" pump installed as well. See picture. It's a little lower than your position but further forward, about 18" or so from the front edge of the tank. I think I'm just going to give it a shot and see what happens. I am guessing there is probably some siphoning action that occurs when fuel is in the pump. I did talk to the people at Carter regarding their P4601HP electric external pump. The guy told me that as long as their pump is mounted with 24" of the tank and below the fuel level it will draw as, according to him, "...the pump does create a tiny bit of vacuum on the inlet side." I am assuming this is the same with the Holley unit as the are both of the rotor/vane variety.

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