I have a 70 chevelle which I think came with a factory 350ci. I am in process of putting a 402 which the person whom is building says it will be approximatly 500HP. I fuel line is 5/16 OD which is 1/4 ID, hes telling me to change fuel line, I notice on all the pick up (sending units from NPD or year 1 that 396-454-and 350's are all the same! so I think I only have to change line not the pick up in tank right? HELP steelworker :confused:

my 72,factory 350/350 came with 3/8" fuel line. Sounds like changing the hard line will get the job done.

500 hp you need at least 3/8 line.call the guys at npd,might not be in catalog.