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Greetings. Looking for anyone who has done the c3 (1976 in my case) Holley 12-312 fuel pump installation? In the planning stages and have the pump and tank is out. Currently the car has hard lines that were pieced in, and I'm not happy with them. My plan is to use Earls Proguard from tank forward with the exception of the tank connection which will be Earls Vaporguard since Proguard can't be used for the tank connection. Interested in any advice. I'm planning on leaving the tank liner in since it is in perfect shape, and I'm looking for advice on how others have routed the line up to the engine and where you put the fuel filter.
I read your thread. Did you run the same pump? This unit is internally regulated and needs no return, which is why I like it. Want to run a 10 micron somewhere in the engine compartment, trying to figure where I'm going to run it up.
No I didn't run the same pump. this is why I have the LS filter/Regulator in the right rear quarter panel. you could put a filter there. or if you want it up front. I would run the fuel line in the stock location. and mount your filter on top of the frame rail just before you cross over to the block. Or mount it right on top of the fuel pump block off plate. Thinking it would be easier to get at on top of the frame rail. run the line across to the fuel pump block off plate. Vinyl covered clip mounted on one of the block off bolts. up the front in the stock location, vinyl covered clip on the head. then off to fuel rail.
On the '82 model year the fuel filter is on the passenger side just about where the frame bends up and inwards at the front (below the heater hoses and such). Might want to just duplicate that setup for ease but other locations will work just the same.
Since this is a recent thread about Holley's EFI 12-312 fuel sender setup, I might as well piggy-back on it,
Yesterday I installed the unit on my '77, keeping my bladder intact. I will be using it with Holley's Sniper EFI. But now I realize I should have asked questions first.
The unit comes by default with some rubber valve, which I left untouched. Is it a roll-over valve? It prevents air/liquid from getting out of outlet B. But since A and B were originally connected to the charcoal canister, this is perplexing since fumes could no longer be sucked out of the tank through B. So a bunch of questions:
- With that rubber valve in place:
* you can no longer connect B to the charcoal canister?
* you can still connect A to the charcoal canister?
* you have to use a vented gas cap?
- With that rubber valve removed:
* you can connect outlets A and B to the charcoal canister as in the original setup?
* you do not have to use a vented gas cap?
An update: I sent the same questions and pictures to Holley and they came back to me and said the rubber valve is there to keep slosh from going into that line. I should have no issue hooking it to the charcoal canister.
But... I then connected a hose to the outlet and tried to suck air out. No way, even though some may say I'm a sucker! I could blow air in but couldn't get any air out, which is what I was afraid of.
So I decided to just stick in a piece of electric cable, just through the rubber valve. Now I could suck air out, and the engine vacuum should too.
Holley 12-312 fuel pump install
