Tim H

I currently am using a 650 DP it is a little rich at idle and puffs black on kick down other wise it runs perfect. Would it be a good idia to rebuild my backup 750 vacuum Holley and use it? Or should I concider some changes to the DP?
Would changing the power valves down 2#s help I am running the factory size jets. This is not really a problem or something I couldn't fix myself but since this board is very useful I might as well get some suggestions.

QuickVet

try working on the carb you have. a 650 should be fine. and it is cheaper to work on one you have then to buy a new one.

ED DINAPOLI

TimH,
I would also suggest staying with the 650. If it is running rich I would reduce the jet size by at least 2 sizes and see if it runs better. The power valve will only effects when the extra fuel is delievered.
Ed

Nomad78SA

I like the 650 also on the small blocks. It will give ya everything you need.
Neil in Tenn

yogi78

Holley's website has some good information in the technical section. If you are running too rich at idle and can't lean it out enough with the mixture screws you might be off the idle circuit, if the float levels are correct you might try cracking the secondaries a very little to see if this helps. They talk about this on the Holley website. Hope this helps. :cheers: