Holley power valve? and blowout protection.

[nitrousdave]

If your fuel pump and ignition check out I would double check the float level. If that is o.k. it sounds like the carb may be jetted too lean. Have you pulled any plugs and if so do they look like you just took them out of the box? If they do that is a good sign that the carb is too lean. I had a stock holley once that did the exact same thing. Put a 650 double pumper on, still had to jet it up and it ran waaay better. Judging from the specs in your sig I would say it is a definite possibillity you are too lean.