My car will be out of paint soon. Have new fuel tank/pump combo and need to run new fuel lines (feed and return). Engine is 714FWHP, LSX440. What size diameter line should I use for both? Stainless, braided or steel? Pro/cons of those materials. Hate to sound like a newbie but LS requirements are new to me. Been out of the game for awhile.

LS engine runs high enough fuel pressure that the stock size 3/8" feed and 5/16" return lines are fine.

Stainless vs. Steel is up to you. 3/8" stainless is a bi*** to bend and can crack when making -AN flares. I used the ni-cop material because it is resistant to corrosion and easy to work with.

Braided hose is used in race cars because it is flexible and doesn't break during an accident when everything gets bent out of shape. But it's not a good choice for a street car. Bottom line is it's just a rubber hose (although some are lined with plastic). The stainless braid will cut and scratch everything it touches. You do need short runs of flex line when going from frame to engine and fuel tank.

Thanks for the info. Wasn’t sure about line size versus pressure. Ready to put this car back together. Went to paint shop today. Car is looking awesome.

I used stainless and rerouted the feed line and fuel filter to effectively eliminate the return line. I used parts store repair parts for the plastic line and fittings. On the engine end I used a russles 05 GTO replacement, its braided stainless and looks great for $25. I have a tool that will allow me to make the factory quick disconnect flare on the fuel line, that's a tough one to come by these days.