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Mar 28, 2010 | 12:41 AM

flywheel

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From: Edgerton, Ks

Return line size

Using an lq4 truck engine with the truck intake (03),what size return line will I need to use with the truck regulator fuel line. Will 1/4" line be OK?...
Rick

Mar 28, 2010 | 05:24 AM

the_merv

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From: The Beach...

I don't see it being a problem.

Mar 28, 2010 | 10:14 AM

LS1GMCTruck

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From: Ft. Lauderdale, Fl.

I''m not 100%, but I'm pretty sure that all the LS series engines need at least a 5/16" return fuel line to the tank.

Last edited by LS1GMCTruck; Mar 28, 2010 at 10:19 AM.

Mar 28, 2010 | 11:03 AM

the_merv

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From: The Beach...

For some reason I remember the feed being 5/16, and the returns being 1/4.

Mar 28, 2010 | 11:21 AM

lsxmalibu

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stock return is 5/16"

Mar 28, 2010 | 11:25 AM

LS1GMCTruck

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From: Ft. Lauderdale, Fl.

I know the '99 & up Vette fuel filter/regulator is 3/8" supply, 5/16" return. Which was the same sizing as my bone stock 1996 GMC pick-up truck, with a 4.3 V-6 in it, had for standard steel tubing fuel line sizing. Not sure, but if my memory recalls, these were outside dimension tubing sizes. Which I remember as being odd, because hose, etc...is always measured as inside diameter. Just pay attention to this when buying fittings & hose.