I have two options, 3/8" or 5/16" from Napa (Autozone and Kragen show the same options). I crawled under car to measure and I am still not sure. There is a difference in cost of $23 (3/8" being cheaper).

Is there any performance difference or fit difference? It is only a 1/6" difference and there is 5" of rubber hose in between the unit and the hard fuel line, so it should fit on there.

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My Swinger gets the Highlight Valet Parking spot over the German sports cars on the Sunset Strip. I love my Mopar.

Stock slant cars got the 5/16" line, the 3/8" was for the performance cars.
If going EFI you might consider the 3/8" version.

The choice is up to you, as your fuel lines under your car will be 5/16".

Good luck,

-D.Idiot

You definitely don't need 3/8". Only the biggest, hairiest, ragged-edge-of-street-driveable big block V8 engines need 3/8". Use the 5/16" and save yourself the hassle of adapting different-size lines.

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