[domeier]

I had a 600 Holley on my truck when I bought it, but I gave it to a buddy when I bought the shiny new Edelbrock. Bad move. I've spent a whole lot of time getting the throttle plates adjusted correctly, not to mention those loose screws mentioned above. Also, there's a lot of slop in the throttle plate shaft. No excuse for that besides lousy machine work at the factory. It doesn't suck air at the throttle shaft (not yet, anyway,) but that's one more thing you should check. You can spray a little carb cleaner at the outer shaft bushings and see if the rpm changes.

Something's still not right if you can't get it to idle below 1100 rpm.

If all else fails, see if any of your buddies are dumb enough to trade you a Holley for it!