Author Topic: Best way to add a fuel return line  (Read 1401 times)

Offline Handyman57

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Best way to add a fuel return line
« on: August 31, 2023, 06:25:17 PM »
I have a 57 Chevy with a 327 , mechanical fuel pump with no return line. Had a vapor lock issue a few times and been told a return line will help. Also planning on adding a fuel pressure regulator.
What would be the best way to add a return line ?  New pump with return, regulator with return, or ??

Offline Cliff Ruggles

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Re: Best way to add a fuel return line
« Reply #1 on: September 01, 2023, 03:39:40 AM »
"Vapor Lock" is a term I have never fully understood and I do this for a living. 

What negative symptoms did you experience a few times?

Offline Handyman57

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Re: Best way to add a fuel return line
« Reply #2 on: September 01, 2023, 05:06:59 PM »
First time out drag racing at the Trifive Nationals Jr stock . Problems got worse in the afternoon temps around 90. Car didn't want to go off the line , then didn't want to accelerate thru the run. Back to the pits would start stumbling and die and not restart till it cooled off. Engine temp 180 up to 210 plus by the time got back to pits. Seem to run fine cooler temps in the mornings, but somewhat hard to start after warmed up. Running pump gas .stock Mechanical Fuel pump, line in stock location, very close to rad hose and block.

Offline Jeff K

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Re: Best way to add a fuel return line
« Reply #3 on: September 18, 2023, 06:10:33 AM »
I always used the 63-64 Pontiac 421 fuel filter. Make sure the two filtered outlets are 3/8" and the fuel return line is 1/4"...

I always took the term "Vapor Lock" as when the metal parts containing the gasoline becoming so hot that they cause the fuel inside them to boil and/or expand to a point were they loose there ability to burn.

Offline Jeff K

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Re: Best way to add a fuel return line
« Reply #4 on: September 19, 2023, 04:05:53 AM »
Back in the early seventies I had a 64 Grand Prix. Wide ratio Muncie four speed, 3.42 posi, 421 and two Carter AFBs. It ran great, it would stay up with the new Crazy KZs that just came out until it ran out of fuel that in the top of second gear.
My friends dad was a port authority mechanic and really knew his stuff. One day I was looking at the engine and he happend to walk by, he took one look at the engine and said; "that big Carter fuel pump needs fed. The gasoline flows to the back of the tank during take off and the car runs until it uses all the fuel in the line, his Saturday, bring the tank down here first thing in the morning.
Keep in mind, this is the most I ever heard this man say in my 25 years of living next to them. He was a big Polish man who did not like a lot of talk ad people who talk too much lol.
I was there, at 6 am. He yanks the big tank out of my hands like a gorella, put it in his stationary tubs and starts filling it with water, then says go home and eat stop back at noon and it will be done.
I come back at noon, he made a sump the tank it had two 3/8" ports. One was capped. It was a work of art. Everything he did was perfect!! I was smiles ear to ear.
After you install it and try it out, bring it down here and we will tune it up. Your running too much advance at idle and I can hear it spit.