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-AN fittings for 5/16" hard fuel lines

Thanks all! The AN919-7-7d male to male black will work with an added 6an to 6an female to female coupler.

FYI...this is not a fuel injection system. This is for qty 2 Edelbrock AVS2 carbs being fed by Carter 4594 thru 3/8 hard line at 5-9 PSI.
The 5/16 return path will have a bleed of some orifice size to dial in a pressure of 5-5.5 PSI based on carb needle/seat size.
Should be easy to adjust PSI, will not dead head the pump, and eliminate the need for a bypass regulator that could fail down the road.
 
Here's a chart for the F to M reducer

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Good morning all,

Question for those familiar with the AN fittings.

I'm in the process of updating my 5/16 fuel line to 3/8 for dual AVS2 carbs on a 440, and looking to use the 5/16 as a return line.
I created a fuel log with -6an (3/8) 37* double flare hard line coming in, and would like the 5/16 37* double flare return at the other end of the log with a gauge.
The problem I ran into was downsizing from 3/8 (-6AN) to 5/16 (-5AN) without converting to NPT first. There are is no straight forward way of going from -6AN female to -5AN male.

I would prefer not to use so many fittings to accomplish this. Converting to brass fittings brings me to 45* brake line flares which could leak.

Can a use a 5/16 double or single flare on a -6an fitting if the flare is on the large side?
If not, any suggestions?

Thanks all!
AN fittings don't work with double flare hard lines.
You cannot use a 5/16 double or single flare on a -6 fitting if the flare is on the large size. Size it correctly or it will not work.
Brass can work but its difficult to work with and its more prone to leak.
Seems your trying to mix and match different style fuel delivery systems.
AN is not required for carbs because they don't need much pressure.
Do not mix AN and NPT
Are you using an electric in tank pump or mechanical?
Most likely there is an adapter -6female to -5 male but why would you want to do this?
If not running an electric pump with regulator then use -6 supply and return.
Hard line is always better than flex but flex makes life much easier.
 
In any fuel injection system with a "Flow and Return", both lines should be the same size, otherwise you will discover all about restriction.

Don't even think about "Dead-heading" the supply line.
I install a larger line on return than pressure.
Fuel pressure to injectors (or carb) is controlled by return flow not pump pressure even though some pumps provide more pressure under more demand.
Up to about 650 HP I use -6 pressure and -8 return
 
AN fittings don't work with double flare hard lines.
You cannot use a 5/16 double or single flare on a -6 fitting if the flare is on the large size. Size it correctly or it will not work.
Brass can work but its difficult to work with and its more prone to leak.
Seems your trying to mix and match different style fuel delivery systems.
AN is not required for carbs because they don't need much pressure.
Do not mix AN and NPT
Are you using an electric in tank pump or mechanical?
Most likely there is an adapter -6female to -5 male but why would you want to do this?
If not running an electric pump with regulator then use -6 supply and return.
Hard line is always better than flex but flex makes life much easier.
I am not trying to mix 2 fuel delivery systems.
I know AN is not required for low pressure carb, but I selected the AN over brass because of aesthetics.
No NPT fittings or rubber lines are being used anywhere in the fuel system
The NiCopp hard lines will be single flared to mate with the appropriate AN fitting.
Carter 4594 external elec pump being used controlled by Bosch relay and inertia switch.
I will test the 6an to 5an reducer with the 5/16 return line that's already there. If this does not provide the control I want, I will either add a bypass reg or upsize the return to 3/8.
 
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