Guys,

I've got a flat spot. Cruising down the road at part throttle, if I quickly open the plates a little, or even if I'm just gradually opening the throttle, I get instant response (pull), dead spot, then pull again (all in a split second). I think it's running out of pump shot as I can feel that get used, then nothing, and then it pulls again. Does this sound like the case?

Or, might this be a power valve issue? It has about 5-6" vacuum at idle and I'm running a 3.5PV.

I'm not a carb guy so if you need more info, let me know.

Thanks in advance,
Steve

try giving Joe Bunetic a call,hes an expert. 1 618 397 3580. Howard

a more aggressive cam or both. Both cheap to try. Doesn't sound like PV to me.

It's a Holley. Dbl pump, not sure of the cfm (milled air horn), I got it used from a friend who said it started life as a 850cfm. Four corner idle circuit.



Right now the jets are 74 primary, and 82 secondary. PV blocked in secondary.



Right now it has a 35 squirter and the white pump cam. I have no idea how to tell which pump cams do what (more or less aggressive). 30cc pump.



Factory dual point dist. Initial is 18deg, with 38deg by about 2500rpm. High volume mechanical pump, about 6psi. Float level at the bottom of the sight holes.



Thanks, guys.

...distributor vacuum advance?...initial timing?...et cetera, et cetera...