-8an feed, 6an or 8an from rail to afpr?

[LIV4PSI]

It makes sense to me to go -8an from the rail to the regulator. I have enough leftover -8an line, and an Aeromotive regulator with -8an inlets. But it seems like most people use -6an for this line. Opinions?

 

[turbowop]

I use -6. Not sure that you'd need anything bigger on the return side.

 

[LIV4PSI]

I am using a -6an return from the regulator to the tank. But bottle knecking the system before the regulator just seems weird to me. Then again, I'm no engineer

 

[turbowop]

-6 is at least the same as stock which doesn't become a restriction until you start making really big power.

That said, you're talking about after the fuel rail anyway. The biggest bottleneck the fuel is going to see is the regulator itself. The little bit of line between it and the rail isn't really going to make a difference unless it's smaller than the opening in the regulator.

 

[DynastyLCD]

5/16" is stock size. -6 is 6/16", what's a 16th of an inch going to change?

stock lines or -6 is good to 600 hp, -8 is good to 1000.

to add to wop's comment - the biggest restrictions are the regulator itself, and the factory banjo bolt coming off of the fuel filter. that banjo fitting really restricts flow, big time. if you'd like to correct that bottleneck, either run an adapter to utilize -6 from the factory fuel filter, or add an aftermarket fuel filter and go -6 from that to the rail.


edit: you have a -8 feed already, that's what i get for trying to read too fast /ubbthreads/images/graemlins/rofl.gif

 

[LIV4PSI]

Quoting turbowop:

The biggest bottleneck the fuel is going to see is the regulator itself. The little bit of line between it and the rail isn't really going to make a difference unless it's smaller than the opening in the regulator.



That's what I am saying, it would be. I have -8an inlets on my regulator, so I should use -8an line from the rail to it?

I probably should have started with the rest of my fuel system and goals for the car. /ubbthreads/images/graemlins/blush.gif Walbro 255 in tank feeding an inline Bosch 044. I am using an -8an feed with an inline Fuel Lab filter, stock rail with welded fittings. I plan to run E85, and hope for an eventual 500whp.

Thanks for the replies Mark and Phil

 

[turbowop]

-6 wouldn't be a bottleneck. The inside of the regulator is what we're talking about. The little opening that holds pressure in the rail and only lets enough fuel through to hold said pressure. Whether you have -6 or -8 before that doesn't really matter.

But if you have -8 connections and extra line, you might as well use it. The only thing you'd gain by using -6 is more space and possible easier routing since the line is physically smaller.

 

[Rausch]

Quoting DynastyLCD:
5/16" is stock size. -6 is 6/16", what's a 16th of an inch going to change?




Where's Barnes. /ubbthreads/images/graemlins/smile.gif