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Stumbling under acceleration

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I had posted a topic under fuel delivery but didn't get a whole lot of answeres there.


Setup is an l28 w/ triple webers, holley red fuel pump, cheap regulator from the auto parts store.


If I mash the pedal it will cut out until I let off. I can go full throttle if I'm nice to it and and gradually step on it.


I had also posted this http://www.racetep.c...fuel-pumps.html


In short it says use a fuel pump with more volume, not pressure, don't run a Vacuum hose into the manifold (which I am) but I've seen people using the same pumps and not have theseen issues.


I bumped the psi from 4psi to about 6psi because it seemed to help a bit.

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Sounds like an accelerator pump issue (not fuel pump).  It a device in the carb that squirts a bunch of extra gasoline in when you "mash" the pedal.  With a bad pump the engine gets extra air but not extra gasoline, and loses power as it leans out.


Not a Weber expert but that's what I'd confirm is working right first.  If the Weber's even use one.

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Most of my experience is with the mikunis but I'll go ahead and try to throw some suggestions out there.


Put fuel pressure back down under 4psi.

Check linkage sync.

Check accelerator pump settings.

Check float levels, are they consistent? Can you raise the fuel level a bit.

Increase pilot jet size.


Got a sync tool? Got a color tune? AFR gauge?

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