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Technical => Spud Miller's Cave => Topic started by: retroboy on November 03, 2021, 02:24:10 AM

Title: Pump speed V delivery
Post by: retroboy on November 03, 2021, 02:24:10 AM
Hello I have an Enderle 80A-1 pump I previous ran with injection. I want to run that pump on a carburetored engine now and have a Holley return type regulator. The pump is still delivering more than needed so I figured I can run a smaller drive pulley and slow the pump a little. If I drop a few teeth off and the pulley ratio is around 10% less does that mean the pump would deliver 10% less or would that be too simple?
Title: Re: Pump speed V delivery
Post by: JEFF/21C on November 03, 2021, 02:10:12 PM
I ran a hilbourn pump with a check valve at 9# with a poppet valve and  =8 return line 950 holley on alky
Title: Re: Pump speed V delivery
Post by: Curly1 on November 21, 2021, 11:33:20 AM
I would not slow the pump down much, I would just return more of the fuel back to the tank. With right check valves you could set idle pressure at 5 or so and have 10 wide open if you wanted.
Title: Re: Pump speed V delivery
Post by: wideopen231 on November 22, 2021, 02:18:21 PM
Running pump slower is fine. It is not linear but close to amount slowed. Only way to know exact would be flow test. If dropping 10% on 7 gpm pump you would loose about .7 gpm. Never slowed one down but have sped them up and they followed that so only stands to reason it will work same.You could just run a pump sizer which basically is just a jetted line to bypass x amount of fuel. Would be easy to adjust and changes are just a jet,spring or shim in a poppet.