Thread: Robbmc option
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Old 06-22-2022, 12:02 PM
78w72 78w72 is offline
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Quote:
Originally Posted by jhein View Post
Not to hijack the thread, and hopefully this is not too dumb of a question, but whis the difference in function and plumbing for a vapor return line vs a true fuel return line?
a vapor return line is usually very small, 1/4-5/16" & is intended to return vapor only or very minimal amount of fuel, its more of a vent for vapor than actually recycling unused fuel.

a true return line like used for electric pumps & fuel injection cars requires a large return line, usually at least 3/8" but some go to 1/2" & say the return should be as big or bigger than the feed line. its designed to constantly return the unused raw fuel to the tank to keep it cool. on high psi elect pump/FI cars most the fuel pumped is returned to the tank since the engine uses very little fuel at idle or light cruising compared to what the pump can & is pumping out. & for these older classic cars that requires running a complete new fuel line vs trying to use the little vapor line they came with.

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