Just got done burning in my cam with a fresh rebuild on my 460( includes new cam, scja heads, edelbrock rpm int, 3500 stall, and all new bearings and what not). While breaking in cam I had the idle @ 2500 and the timing was around 30 deg w/ vacuum disconnected from dizzy. Then I tried to back down the idle to around 1k or 800 and the thing would not stay running. The new cam specs are 224 @ .050 int & 234 @ .050 exh, .540 lift int & .560 exh. It is a howards cam part # 240041. They told me it is pretty much the biggest cam I can run and still have vacuum for the brakes( so hopefully that is true). When I get the engine down to around 1300-1500 rpms it will stay there and run but anything lower it will die. When I am at that rpm I have around 15 deg advance. I am using a MSD 8477 dizzy (with the red bushing installed 28 deg and one heavy silver spring and one light silver spring) and a 6a box to power it. The carb is a holley double pumper 750 p/n 4779-6. I have around 7 psi of fuel running to the carb, and both the idle mixture screws in the front metering block are 1.5 turns out. The front main jets are 74 and the rears are 84, even thought that shouldn't have anything to do with the idle. Also there is a 3500 stall behind the eng. So the question is what is the correct procedure to set up idle, and what rpms should I be expecting @ idle with that cam?