Just pulled a Holley off the car, going with a different set up. What's the best way to drain/flush the carb? My plan is to use it on the big block next year so it'll sit on the shelf till then, don't want it to gum up with old gas.

What I'd suggest is take off the bowls/metering blocks/plates/squirters/mixture screws (especially them)/everything & blast every passage with a 2 dollar can of brake kleen (use up the whole can)

yep, I open them up, wash them out with brake clean, spray them down with wd-40, install a fresh rebuild kit, seal it up in a big plastic zip-lock bag, then shelve it. ready to run.

if it is only going to be weeks, then I just dump it out, pump the fuel out the pumps and shelve it.

I have intakes that they sit on with air cleaners to keep them sealed up while on the shelf.

I have blown them out with light air pressure, several times in the fuel inlet and the bowel vents, everywhere to get all the gas out of them off the motor. Sprayed some wd40 in the same openings and gave it another light blow. Plastic bag, worked for me.

Hmmmm.

I do nothing but drain the fuel out.

For a year I agree for longtime storage suggestions above sure cuts down on all that white crap growing inside & corn fuel eating rubber parts.

Just don't turn them upside down to dump the fuel and stir things up and clog the jets

I'd pull off the bowls AND all of the plates and gaskets. I've found gas behind the metering plate gasket on a vacuum secondary holley, in the hollow area where a power valve might go on the primary side of a carb. That gasket did not have an opening in it for the power valve but there was still gas behind it.

I've had good luck dumping the gas out of the vent tubes and filling with sea foam. Work the accelerator pump and slosh it around inside and dump the excess and bag it