Im just about to install a new Holley 110 mpg fuel pump and ran into a little problem. The current fuel pump has 3 inlets on the pump as the new aftermarket pump only has 2. What do I need to do to make this work? Two of the lines are leading to the gas tank and the other to the carb. Do I need both of the tank lines?
Any help would be appreciated. Thanx DUECE

 

I'm guessing that you meant to type "110 G.P.M." fuel pump. If not, I really need to get some of those "110 mpg" pumps to improve my fuel mileage. That's O.K., since it's taken me about a half hour already to type this much of a reply with two fingers...

The original pump had a suction line to draw liquid fuel from the tank, a discharge line to deliver fuel to the carburetor, and a return line to allow excess fuel AND fuel vapor under pressure to vent back to the tank. This supposedly helped to prime the pump and minimize vapor lock possibilities.

Your replacement pump is probably not a positive displacement type, so it will maintain its design output pressure without the need to return excess fuel to the tank (like the stock Chevy pumps did for decades). You should be able to cap the extra vapor/return line to the tank and use the pump without problems. If you experience vapor lock in hot conditions, you'll know why. I doubt that it will be a serious problem unless your fuel line routing takes them too near the exhausts.

 

Thanks Vader , but which one do I cap bro? The one closest to the motor(fatter one) or the other. thanx for the info, I was afraid I was gonna have to return it. Also the new holley pump's inlets are not exactly matching up w/ the line to my filter/carb hose, is there any way I can rotate the new pumps mainbody to match them?DUECE