PTFE fuel line sizing

All the PTFE line I have looked at has a smaller ID due to the PTFE liner (I guess..) so is it necessary to upsize when running PTFE line? I bought some -8 for feed and -6 for return for my efi application. It looks smaller so I measured the fittings (smallest ID) and it is maybe 1/32 smaller ID then the regular Fragola fittings. The -8 is more like 3/8 and the -6 is 5/16. There is lots of OE cars making 1000 hspr on stock 3/8 fuel lines (efi) which is way more then I am making so in theory I should be good. Just curious to other peoples experience.

Not that I'm anywhere near a definitive answer, but I though in fuel lines the restrictions were the fittings, followed closely by bends. Ptfe doesnt bend nearly as far and the fittings I've seen are using compression fittings which arent as restrictive. I would like to know possibly from a vendor the actual facts

Jason

-8 Teflon innertube steel braided hose throughout my car: Feed and return

litshoot wrote:Not that I'm anywhere near a definitive answer, but I though in fuel lines the restrictions were the fittings, followed closely by bends. Ptfe doesnt bend nearly as far and the fittings I've seen are using compression fittings which arent as restrictive. I would like to know possibly from a vendor the actual facts

There is still a barb that goes in the hose that the furrel clamps down on but so the smallest ID in the system is the ID of the fitting.

I guess it is just a mental thing where you think I have -8 or 1/2 fuel line and it really isn't. lol.