71duster06
Well-Known Member
What does everyone use/setup for a fuel return line? Any pics would help. Currently I dont have one and would like to know if it is required or "should" be installed.
Thanks
Thanks
Fuel return line?
- Thread starter 71duster06
- Start date
-
Yes, you need one.
71duster06
Well-Known Member
Do you have any pictures of your setup? I assume that a T fitting is required before the carb inlet. I have an electronic fuel pump now at 7-8psi. Also where on the fuel tank does the return line go to?
I just either run a sending unit with an extra inlet for vapor return, or drill and weld in my own nipple. I said nipple. PM me if you want to know the rest of my recipe. I've been blasphemed about it before on here but it works like a ****.
jdakota
Well-Known Member
I just read an article about the new generation of fuel pumps that don't require a return line. I'm not sure which magazine it was in, but I think it was Street Rodder or something like that. If you haven't bought your pump yet, it is worth looking into.
Seems to me you said something about a write up on that about a year or so ago, I musta missed it.
stumper
Well-Known Member
Just put a new Holley HP 150 on my car and after talking to their tech people they siad the return was not needed with their pumps. They have an internal recirc system in the pump. I think many other electric pumps are the same these days?
67Dart273
Well-Known Member
One problem with a MOTOR DRIVE electric pump is that the continually heat and foam the fuel. With a return line, this is alleviated. There is NO WAY I'd run that Holley 150 GPM WITHOUT a return from the regulator
Even if you run alow pressure (as Holley Red) pump not requiring a regulator or return, A VAPOR RETURN is a tremendous idea and REALLY helps in the vapor lock/ fuel boiling dept.
FIrst one I ever saw was factory on my 70 440 six pack RR. IT WORKED.
It is VERY easy to implement one if you have a newer car with a garbage, er I main carbon canistor, and are able to delete it. Now you have a return line
On my 67 I had to add one. I plumbed CO2 from my MIG to the fuel delivery line after siphoning the tank down, and temporarily brought the vent line (extended) out from the trunk. The CO2 at very low pressure was acutally pushing fumes and vapors out the vent, the highest place in the tank. So I lit it, and let it burn off until it went out -- indicating combustible vapors had been purged. I then let it run another couple minutes for safety.
THen I removed the cap and allowed the CO2 to continue. Too a sharp punch and made a hole in the tank face above and to the side of the sender, and then stuck a stub of 1/4" tube in the hole, and just silver - brazed it right in.
For the return, in my case, don't have a regulator, I only wanted vapor return. So you can use Wix filters -- built in. They make a 5/16 filter and a 3/8 filter with a built in 1/4" return line with an orifice built in. You can mount/ lay the filter either vertically or horizontally so long as the 1/4" fitting is AT THE TOP
Wix no. 33040 for 5/16, 33041 for 3/8
Even if you run alow pressure (as Holley Red) pump not requiring a regulator or return, A VAPOR RETURN is a tremendous idea and REALLY helps in the vapor lock/ fuel boiling dept.
FIrst one I ever saw was factory on my 70 440 six pack RR. IT WORKED.
It is VERY easy to implement one if you have a newer car with a garbage, er I main carbon canistor, and are able to delete it. Now you have a return line
On my 67 I had to add one. I plumbed CO2 from my MIG to the fuel delivery line after siphoning the tank down, and temporarily brought the vent line (extended) out from the trunk. The CO2 at very low pressure was acutally pushing fumes and vapors out the vent, the highest place in the tank. So I lit it, and let it burn off until it went out -- indicating combustible vapors had been purged. I then let it run another couple minutes for safety.
THen I removed the cap and allowed the CO2 to continue. Too a sharp punch and made a hole in the tank face above and to the side of the sender, and then stuck a stub of 1/4" tube in the hole, and just silver - brazed it right in.
For the return, in my case, don't have a regulator, I only wanted vapor return. So you can use Wix filters -- built in. They make a 5/16 filter and a 3/8 filter with a built in 1/4" return line with an orifice built in. You can mount/ lay the filter either vertically or horizontally so long as the 1/4" fitting is AT THE TOP
Wix no. 33040 for 5/16, 33041 for 3/8
inkjunkie
Well-Known Member
Just wondering, lets say you were to put a "T" between a regulator and the carbanator. Should you run a restricter of sorts in the return line in order to avoid bleeding off the pressure at the carbanator??
demon seed
The Original Demon Seed
Usually if you want to run a return line you purchase a regulator that has the return port built in. just an example
http://www.summitracing.com/parts/QFT-30-900/
http://www.summitracing.com/parts/QFT-30-900/
I was going to but the apparent disdain for my fuel system design put a quick stop to it. I've done it that way for 20 plus years and gotten really close to TBI performance with a carburetor.......but people don't want to hear about it.
the only lines i have coming out of my pressure regulator, are to the carb, and one to the nitrous system. i have NEVER had a return line on my street strip dart, that was clear back to a 318 with an engine driven pump, all the way to the 408 thats in it now with a mallory 140 feeding it. granted i never set out for road trips in it, but i've never had an issue. however my old 1986 chevy truck see's hour+ trips sometimes, and it has a little electric fuel pump regulated to 6 psi, again no return. it's bone stock and kept eating fuel pumps, so it got an electric pump, a regulator, no return line, and has been happy ever since.
the science between churning up the fuel and heating it makes sense with no return, but with the above gas hogs, i doubt the fuel stays in the lines long enough to matter.
the science between churning up the fuel and heating it makes sense with no return, but with the above gas hogs, i doubt the fuel stays in the lines long enough to matter.
67Dart273
Well-Known Member
You could be correct about that detail, but a orificed Vapor return, even if you don't run a regulator return, will help immensely with Vapor lock and fuel boiling.
-
