...so I chewed up the rubber return line going from the hard lines to the sender at the tank. ....they just didn't wanna come off! ...anyhow I've read several posts saying there's really very little pressure, but that you still need to use EFI line. I've got a bunch of fuel line already, but it says not for EFI. ...I had assumed that was in reference to the pressure, but it kinda sounds like I need something else.

Can someone confirm? Do I need special fuel line?

 

Your TPI fuel pump probably makes about 60 PSI. Your regulator creates a semi-closed system in the feed lines and the fuel rail. The FPR regulates that fuel pressure by bleeding off some of the high pressure to the return line. There is no restriction, other than the diameter of the line and the length of that line in the return line so little pressure is built up in that part of the fuel system. Could you use regular fuel line? Probably, but why? Can't you get the correct replacement line?

 

Well because I had it already. ......but I just ran out and bought some new EFI rated fuel line, just to be safe.

My question still remains, although only theoretically now.....if there's no pressure (minimal of course) then why does it need to be "EFI" fuel line?

 

EFI fuel line is going go be gas safe, and pressure-safe for higher-than-TBI pressures.

Full-circle stainless EFI clamps are fine for the return system, and it sounds like you got the right hose.