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Hi all, does a blower motor w/ carbs need a return fuel line??? I'm going to need to up-grade my fuel system to install that Hemi in my '32. I only have a 3/8" outside diameter fuel line now so I think I'll need a bigger fuel line, I need to get an electric fuel pump, filter, etc. When I run my fuel lines in my frame I'm wondering if I need to have a return line. Thanks! ;) Bill
Hey Bill you shouldn't need to run a return fuel line as long as you are running a fuel regulator with your fuel pump.I run at 6 pounds on my regulator with two 600 Holleys and have the blue Holley pump.I think you may need to upgrade your fuel line though as 3/8" OD is a little small,I run a 3/8" ID.Hope this helps.:D
....Thanks a bunch Blowby. Good that's easier if I don't have to run a return! ;) Bill
I do run a smallblock though so am not sure what the Hemi guys would run for fuel line diameter.I am sure someone with a big block will pipe in.
When you get a fuel system big enough to run a blown '92 you'll need at lest a 1/2 or possibly 3/4 fuel line and a big bypassing regulator ( possibly hooked up after your float bowls)to return excess fuel at lower throttle settings.
The holley pumps probably won't be big enough
Of course if you use a mech engine driven pump this all changes
Thank You Blowby & Jerry....
Jerry, what kind of electric fuel pump & fuel filter would you recommend? And I will run 3/4" line if you think it's necessary {is that what they refer to as a
-10 line?}. I'd rather be safe than sorry. What size return fuel line would you use?... You mentioned a mechanical engine pump? Would this feed this size engine? If so, what make/model would you use? THANKS ;) Bill
Those lines are measured in 16ths. A # 10 line is 10/16 or 5/8. A #12 line is 12/16 or 3/4"
the return is more to help keep the pump from dead heading and heating up the pump . bigger the pumps the more you should think about a return .i am doing a anglia blown 383 using a big pump with a return regulator by pass log using AN10 for a feed and the AN8 for the return. if you use the smaller blue holleys pump you will not need a return.i have used many on the street you will run out of road before you run out of fuel. my chevy is a 548 with one blue holley on it. i know for wide open it could use more carb s with bigger cfm and more fuel bigger pump but i never get to that point on the street. all out drag racing is a new game you would want fire size hose and the pumper truck to:D
...hummm, Thanks Jack, that takes the 'mystery' out of it! 1/16" for every -1......
...Thanks Pat, I will go with the bigger line {like 5/8"} w/ a pump that's bigger than the blue Holley. I'm getting another fuel cell & running new lines & getting a new fuel pump I might as well go 'all out'.......
Bill