Carburetor fuel line diameter

tony-muscle · Dec 14, 2016

Does anyone know the diameter of the fuel line from the pump to the carburetor? (I have a 351-4V). Mine is 5/16" but I am second guessing since the line from the tank to the pump is 3/8". I have no idea if mine is original or replaced.

red351 · Dec 15, 2016

Yes 5/16"

Stanglover · Dec 15, 2016

Yes, 5/16 is the original diameter, but if you are upping your HP, a 3/8" has been recommended. Also, as I now have a Holley on my 4V, I am replacing the pump to carb line with 3/8" to get rid of the rubber line I have to use across the front of the carb to join the 5/16" line to the carb. It looks messy to say the least and I can make it a direct connection with the appropriate fittings.

tony-muscle · Dec 15, 2016

Yes, 5/16 is the original diameter, but if you are upping your HP, a 3/8" has been recommended. Also, as I now have a Holley on my 4V, I am replacing the pump to carb line with 3/8" to get rid of the rubber line I have to use across the front of the carb to join the 5/16" line to the carb. It looks messy to say the least and I can make it a direct connection with the appropriate fittings.

Do you know if they sell a 3/8 repro? Or I might as well make it myself. I wonder if I should keep steel tubing or change to a braided hose.

1971 M-code Mach 1

Stanglover · Dec 16, 2016

Yes, 5/16 is the original diameter, but if you are upping your HP, a 3/8" has been recommended. Also, as I now have a Holley on my 4V, I am replacing the pump to carb line with 3/8" to get rid of the rubber line I have to use across the front of the carb to join the 5/16" line to the carb. It looks messy to say the least and I can make it a direct connection with the appropriate fittings.

Click to expand...

Do you know if they sell a 3/8 repro? Or I might as well make it myself. I wonder if I should keep steel tubing or change to a braided hose.

1971 M-code Mach 1

Don't think so and if they do, it will likely be the same as original for an Autolite carb. I will need to make it up as its' going to be longer, but I'm hoping to find a length of ready made fuel line tube so I don't have to piss around with flare tools although that may just happen anyways.