Accelerator pump size

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slowdown

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i have 2 750dp Holley part#80573s an they have the duel 50cc accelerator pumps. My question is are these pumps to big? The racier 750dp part#80576s has 30cc pumps and that’s got me to thinking. Should I be starting with smaller pumps. Ive been driving it around town an it’s crazy but may be a little rich yet. But it doesn’t spit sputter or bog an I haven’t fouled any plugs. So I’m just not sure if smaller pumps would matter in my case. And I don’t know if I would gain anything. Any thoughts on this would be appreciated. Thanks.
 
I can’t see any numbers but there red if that can tell you anything. I will have to look at the site an see if it says what size there shipped with.
 
Depends on the cubic inch. My 318 gets by with dual 30s but the 390 has a 30 primary and a 50 secondary. You can change jets up and down to accommodate. The truck goes to an immediate 11.0 as soon and it is at WOT. But then settles in to a 11.8-12.2 once the rpm come up. With the 50cc secondary it would bog to a 10.0 and never really recover much past a 10.9.
Just use what works the best. Read the plugs.
 
I can’t see any numbers but there red if that can tell you anything. I will have to look at the site an see if it says what size there shipped with.
They accelerator pump cover will be deeper. The arm is different also
 
Pumps are for launch, jets are for WOT. I run 50cc pumps and pink cams and they are the most adjustable also the squirter nozzle makes a big difference.
 
I actually just looked at my carb online just so I could tell you what accelerator pump size I run and cant' seem to find it listed anywhere.
 
An AFR gauge really helps with accelerator pump rigging. When stomping the pedal, you should see 13.5, when you stop it should transition easily into wot mixture, usually 13-13.5. There shouldn’t be any fluctuations or lean outs, nothing over 14.

Ignition and timing health play a big part in this too and should always be checked first.
 
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