Return Fuel Line- dead head regulator

7

73c34me

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Laingsburg, MI
Greetings, I am installing fuel lines and on my carbed motor. Does it make sense to install a return line on a holley dead head regulator that is supplied by a holley blue electric fuel pump? I seem to remember something about installing a return line that is regulated by a holley jet, to provide benefits ofh smoothing out fuel flow.
 
No idea about the electric pump but .....with most aftermarket mech. pumps you need to run the return line from the external regulator because the pump does not have an internal regulator like the stock pump.
 
Have used those regulators for years, but not with electrics. They don't keep a very well regulated pressure unless a return line is used and then I don't really like them. You can use it that way though, I wouldn't.

Have also made my own regulators making a block fitting that accepts a carb jet that can be drilled out to suit. But again not with an electric pump, which shouldn't make a lot of difference anyway. Some trial and error with this method, but I like it better. Pretty foolproof. Since it doesn't use a spring etc, you have to adjust the oriface size for higher rpm, since that where it needs the most flow anyway.
Despite recommendations, I like to keep the pressure down at around 4 psi. It's the pressure consistancy that makes it work better.
 
Can you share what orfice size jet & what the motor is your feeding? I was pretty certain i had heard of this method before, thanks for responding.
 
Used on base engines, with both qjet aand holley and mechanical pumps, but that shouldn't make much difference.

Make a steel block out of a short 3/4" rod.
Drill 3 3/8" holes for flaired brakes lines to use as fuel lines.
Flare a bubble on the one for the return and either gas weld it almost full with braze or 70s steel rod.
Drill and tap for a carb jet or a longer brass allen set screw.
Drill jet or set screw for proper size. I think I used .040". Test for the lowest pressure without leaning or stumbling engine. Don't believe the recommended minimum carb fuel pressure. Just make sure float level is proper. I think I ended up with around 2# at idle and around 4# at rpm with no problems.
Better to drill a 4th port for a fi fuel schraeder valve to temporarily connect a decent fi fuel pressure gauge to test at all rpms.

It ends up being very consistant and should work well with an electric pump. My mechanicals already had a return in them so you may have to go bigger than .040".
 
:bonkers::yahoo:Reading last post here by 010752 makes me thimk a bit...

suppose we take basically ANY kind of fuel pump and a 3/8 OD line for conversation sake, and push fuel to ANY carb....and the line from the frame comes up to a horizontal tube, in that tube is a T with full 1/4 inch ID holes all 3 ways....so the inline goes from source to carb directly....the stem goes up and over to the return....surely the float will be able to force any fuel to the return easily....but.....when the valve is closed, or even partly closed, the fuel runs up and over to the tank in the same sized line it arrived in....

I think it would work long as the top of the up and over point was higher than the fuel tank return spot...typically top of the tank....

anyone??? no regulator needed, let gravity do the work....

what am I forgetting???

curious question, and a spur/moment thought....

:yahoo::beer:
 
010752 said:
Used on base engines, with both qjet aand holley and mechanical pumps, but that shouldn't make much difference.

Make a steel block out of a short 3/4" rod.
Drill 3 3/8" holes for flaired brakes lines to use as fuel lines.
Flare a bubble on the one for the return and either gas weld it almost full with braze or 70s steel rod.
Drill and tap for a carb jet or a longer brass allen set screw.
Drill jet or set screw for proper size. I think I used .040". Test for the lowest pressure without leaning or stumbling engine. Don't believe the recommended minimum carb fuel pressure. Just make sure float level is proper. I think I ended up with around 2# at idle and around 4# at rpm with no problems.
Better to drill a 4th port for a fi fuel schraeder valve to temporarily connect a decent fi fuel pressure gauge to test at all rpms.

It ends up being very consistant and should work well with an electric pump. My mechanicals already had a return in them so you may have to go bigger than .040".
Click to expand...

That is a very good idea,and simple to make and install. with my stock fuel pump with a return line do i need to have a pressure regulator,seems to be keeping up with 750 dp quite fine. My fuel rail has a port for a pressure gauge,anybody have any gauge prefrence that they like? i realy don't need it just a thought and a hole to plug :amazed:
 
Unless you think you have fuel delivery problems, my thinking is that every connection/port is another chance for a leak. I've got a stock (aftermarket) Airtex pump on Ol' Red, and it's never offered to run out of gas. (as long as I keep some in the tank)
 
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