Carburetor 4 barrel quaterjet rochester how do set complete

Screw in the idle mixture screw until it stops aNd STOP! Do NOT attemp to tighten it or you will ruin the tip of it (its tapered and sits in a tapered seat). Now back it off 1-1/2 turns and you have a starting point. Youll have to figure out the idle screw yourself but 800 rpms should be a good speed to start with. As you adjust the idle mixture screw the idle will change so youll have to keep adjusting both together. To set it properly youll need to have at the very least a vacuum gauge but you should have a dwell meter, tach and a timing light too. Super Chevy Magazines has a online guide to Rochester Quadrajet carburetors, its a very detailed and compete guide