hmm i was looking at my fuel line and it looked like 5/16. Ill have to get the drill bit out and find out. I read the rules and you are able to upgrade to 3/8's line

1971 Plymouth Duster 340 auto
1937 Plymouth PT50
1969 Dodge Dart Swinger 340 4 speed
2013 Ram laramie 2500 hemi
2008 Harley FLSTSB springer