Fuel line question

[1969superbee]

I need some advice on fuel line size to a 440 six pack engine. I am going to run 3/8 line from the tank to a filter then to the pump and regulator. My question is being the feed lines to the carbs are 5/16 on the six pack set up where do I need to stop with the 3/8 line? Do I run the 3/8 all the way to the 5/16 carb feeder lines? Where is the best place to put the regulator or does it matter as long as its past the pump?

 

[66Satellite47]

It all depends on what your whole set up is. The OEM lines are 5/16 from the mechanical pump up to the carbs. I think the conversion to 3/8 happened on suction side of pump (not sure). If you're using the mech pump, why the regulator, it's just a flow restrictor? When we used these setups for drag racing with electric fuel pump & regulator, we up sized lines going to the carbs to 3/8 & 1/2 from regulator back to electric pump.

 

[1969superbee]

I'm running an electric fuel pump and was wondering what the downside would be to running 3/8 line all the way to the 5/16 at the carbs.

 

[lewtot184]

ther's no down side in running 3/8" line from the pump to the carbs. the issue is fabbing one because nobody makes one. putting a filter between the tank and the pump is a no-no unless it's something like a 100 micron screen. here's a pic of a 3/8" 6-pak fuel line i made sometime back.

 

[Meep-Meep]

You will be fine with 5/16" lines at the carbs. If running an electric pump put the regulator in the engine compartment and the outlet side of the reg can be 5/16" to match the carbs. If mech pump run 5/16" on the pressure side to the carbs. The Holley needle and seat assembly has about a .100" hole to allow the fuel into the bowl and that is your biggest restriction so unless you are making a ton of HP don't worry about it.