I have heard before, and have been told mutliple times here lately, that if I'm running a return style system with -8 feed, then I need at least -10 return.....but I've read in many places where LSx guys run -6 as a return.....

Someone please explain this to me....

-Will

 

I am running -8 feed and -6 an return. Many people run this combo for 800 to 900 rwhp.

Keith

 

Keith is right - most people do a bigger feed than return. I've got -8AN for both.

 

I can't ever think why you'd need a bigger return than feed line. So if you've got a -8 feed, use a -8 or -6.

 

If you look inside an EFI regulator, you would see the bypass orifice is only around .090" diameter... so no real neef for a huge line connected to it. Generally, it is always safe to use 1 size smaller return line than the needed supply.