Holley Fuel Regulator

I am ordering a new fuel tank pick up from RobbMc with -8 pickup for my Maverick. I found a Holley fuel regulator on the car with the part number 34R-6657B. I want to run a bypass line back to the tank. I cant find any information on this regulator to tell if it can be used for bypassing fuel or just dead head to carb.
I am planning on using a 100 micron filter pre pump and 40 micron after. Does this sound right to you guys?

Thanks for the help.

Tom

That's just a casting no, not a part no. It could be either a 12-803 which has 3/8 NPT ports and a .220 restriction, and is adjustable from 4.5 ro 9 psi, or it could be a 12-804 which is identical, but regulates from 1-4psi. I don't think you'll be able to tell by looking at them. You'll have to hook it up to a guage and see what it puts out. If it's chrome, the part no's are 12-501, adn 12-500, respectively.

I did some more searching and found that these old regulators look almost identical. There looks to be 2 kinds. Bypass and non bypass. The way you tell is if both horizontal outlets are just that, then it is a non bypass regulator. If one the horizontal outlet and one horizontal inlet, then its a bypass type.

I don't know if the old regulators are marked inlet - outlet....


I also found I was running a 35 micron filter before the pump... Bad.. It was the Earls type with the bronze filter.

Tom