A few electric fuel pump questions

yeah i'm also intersted in knowing that.

 

A 2 pipe system is the better way to go.
The pump never labors as much as dead headed and no air problems.
An adjustable restriction on the return line (regulator) gets the operating pressure the carb needs at no more than 7 psi.

 

this works real well.

 

Can i run a return line back into the top of the tank where the vent line is?

I currently just have a small fuel filter on a 6" long tube to keep fuel from splashing up out of it. That is how I am venting my tank. I think my cap is vented too...

 

The vent line fitting in the tank usually has a check valve in it so you would have to eliminate that. Then you would have to get vented cap or make yours vented.

 

When i modified the vent, it was completely clogged and gunked up, so I drilled in from the front and bottom, so if there was ever a check valve in there, there isn't anymore...When I blow into the inside of the gas cap, air comes out so I am guessing it is vented. It has a small hole on the inside of the cap.

If it is not truly vented, I could make it so pretty easy...

So, all systems GO on a return line?

Do I run it out the plugged side of the regulator (closest to the fender) or would I then lose the regulated pressure to my carb?

PS--old picture, I now have braided stainless lines, etc...

 

I agree with Mavaholic. I would also add that that size opening may be too small for a return. Depending on how much fuel you are returning to the tank.

 

With that style of regulator you would have to put an orfice in it so it doesn't dump all the fuel back to the tank and cause your pressure to drop to nothing. Kind of like having the same sized opening in both ends of a balloon. Anyhow, to do it right you need a return style regulator like the Mallory or Aeromotive. All you will acomplish with a holley regulator is to heat up your fuel and to get rid of some of the tendency to vapor lock.

 

What about using the line going to the charcoal canister in the engine bay?
Would that line not make a perfect return line?

 

That's the line with the check valve in it. The way it's set up it won't let anything go into the tank, but will let pressure escape through the canister. The cap allows air into the tank. Actually summit sells a kit that you can put into your filler neck for a return line. http://store.summitracing.com/partdetail.asp?autofilter=1&part=MOR%2D65385&N=700+115&autoview=sku

 

As far as wiring the fuel pump goes be sure to hook it up through a vacuum or oil pressure switch. If you have a fire and your engine quits but the fuel pump keeps pumping it is going to be a very bad day. The vacuum switch has two poles and the oil switch has three.