Originally Posted by TJP
Do your mixture screws respond ?? If not you might want to take a look at your off idle transition ports with respect to the primary throttle blade position when off choke and against the idle stop screw

What kind of carb ??. I


Yes, if I turn the screws in, I can kill the motor.

I think I checked the transition ports a while back but are you thinking that I have the idle too high and I'm not on the idle circuit anymore?

It's a Holley 4150 with vac secondaries.