Fuel Line Installation - MK4

[rsbrillhart]

Ready to install the fuel lines(s), but have a few questions I couldn't find specific answers to searching the forum. I'm running a Blueprint 347 with a Holly high performance carb and a Holly electric fuel pump.

1. The pump instructions suggest a 2nd fuel filter (40 micron) installed after the initial filter and pump. I wasn't sure what the FF supplied filter size is and if this second one is needed.

2. Being a low flow pump, it says a regulator is not needed, but wanted to confirm here.

3. Is a return fuel line needed in this set up?

4. The Holy pump notes that it's not legal for use in CA except on pre-emission controlled vehicles (pre-1986). Does that apply to these vehicles?

Thanks all.

Randy

[Boydster]

Hey Randy,

1. Any external electric fuel pump should have a pre and post filter. I believe for a carb, you want a 100 pre and a 40 post. I dont know what the F5 supplied filter is, but its designed for EFI. An in-tank pump has a 100 micron pre filter installed ("sock") and then uses an external post filter.

2. Depends on the pump. If it self regulates to a pressure within the spec for the carb, you're fine.

3. The return line returns excess fuel from a regulator.. No regulator, no return line.

4. Dont know where you are... if you're not in Calif, no big deal. If you are, that place is a whole 'nother ball of wax and someone thats been through the legal process needs to answer that one.

Good Luck!!

[BB767]

"4. The Holy pump notes that it's not legal for use in CA except on pre-emission controlled vehicles (pre-1986). Does that apply to these vehicles?"

No. Under SB100 you will be a 1965 model year.

[rsbrillhart]

Thanks for the responses. I do live in CA so that's good news. Also, appreciate the advice on the filters.

[phileas_fogg]

Forgive me if I'm telling you something you already know, but if there is a model number stamped on the F5-provided fuel filter (or maybe the box), Google will quickly find its specifications for you. I've used a search to find out all sorts of stuff about my car (and along the way, found I needed a different fuel filter to support my Holley EFI system).


John

[rsbrillhart]

Thanks again for the responses. A new related question that I hope I can continue here without starting a new thread.

The Holly electric fuel pump that came with the engine says it must be installed as "near as possible and BELOW the fuel tank", presumably gravity fed to the pump which then pushes it to the engine. Locating the pump below the tank is going to be a bit of a challenge and my question is whether that's necessary? I would assume the pump will create some vacuum and "pull" the fuel out of the tank and into the pump. Is that accurate?

[frankb]

Speaking from experience, the fuel pump must be located below the fuel tank (fuel level actually). Especially in hot weather, if the pump is above the fuel level you will experience vapor lock (loss of fuel to your carb) as the fuel vaporizes due to the suction pressure at the pump. I mounted mine in the wheel well area, forward of the axle and plenty inboard to avoid contact with the rear tire.

118087

[rsbrillhart]

Thanks, your picture is helpful. What did you use for the bracket and did you rivet that to the 2x3 frame section?

[frankb]

I used an aluminum plate, approximately 6" x 6" x 1/4" and riveted it to the 2 x 3 tube using 1/4" dia. blind rivets, the same ones used to rivet door lock solenoids into position. Note that the pump can be heard when the ignition is on and the engine off, but once it starts, not so much! :)