Just trying to clean up the surge tank system that the previous owner installed on the car, he used rubber lines for the surge tank and return system which I want to convert to SS lines with AN fittings.

What size is the fuel return fitting that is on top of the fuel pump basket?

I want to buy the quick disconnect AN fittings as seen in the picture below. (the fitting on the top). Just want to make sure I order it for the right size.




If the above question/picture isn't clear, below: looking for the diameter of the 90 degree fuel feed port on top of the fuel pump basket.

 

It will depend on the fuel system. On my CJM kit it's an AN -8 size.

A little trick I've picked up is to measure one of the fittings six sides - put that into 16th of an inch and that will tell you what AN size it is. It's not exact and there are some inconsistencies between brands and sizes but it can help you get close.

AN 3 = 3/16"
AN 4 = 4/16" = 1/4"
AN 8 = 8/16" = 1/2"
AN16 = 16/16" = 1"

This is a AN -8 and one side is approximately 1/2"

 

Thank you for your reply, but I am looking at the diameter of the plastic outlet on the fuel basket pump and not the AN fittings.

There are AN fitting adapters for those outlets, they either come in 3/16 or 5/16 size. Trying to find out which one is the right size to get.

 

Pretty sure the feed size is a 5/16".

 

That is what I was looking for! Thank you!

 

I'll measure mine and get you a picture if you can wait until tonight to confirm...but 5/16" does seem right...

 

Russell, 640940 3/8 fitting. Haven't installed my surge tank, but have test fitted the fitting.

 

Are you sure it is nice and sealed? 3/8 is bigger than 5/16, is there a chance that it might not be the exact size?

By the way, which surge tank system are you installing?

 

I think the ID is 5/16" the OD is 3/8"...Terra is on his game...

 

Great info! Thank you!

 

http://www.summitracing.com/int/parts/rus-640850

I am guessing then we are looking at these.

On the phone with Russell now to make sure the diameter they indicate is the O/D and not I/D

EDIT: Russell says go with the O/D. So as Terra suggested.

Thanks for everyone who has chimed in on this thread.

 

Generic tank, aeromotive regulator and a walbro 255. Keeping the system return less for now. I want to end this stupid fuel starve issue, I can't even run 2 full sessions from a full tank without getting fuel starve in the last 5 minutes of the second session.

I have everything ready to go, just need to build a way to mount the tank, figure out how to run the lines in and out from the OEM tank and seal the area and a cover panel for where the glove box was