460idle problems?

my problem,
I have a ford 460ci fitted to 1961 fairlane,engine rebuilt with keith black pistons,[1vr], comp 10:1,edlelbrock rpm heads,edelbrock rpm cam kit,edelbrock rpm inlet manifold,holley 800cfm double pumper.
The problem is that when off idle is fine,revs hard, but at idle,runs rough and the smell/fumes from exhaust make your eyes water! adjusted secondry blades to give better idling using the stop screw,but this car has vacuum wipers and now they now dont work unless you rev to 3000rpm.[wipers worked fine before rebuild].
I have heard that the rpm manifold works better with spreadbore carbs,as i have a square bore carb,does it need a spacer,or i have a edelbrock torquer manifold,would this be better to fit? and give better vacuum.rpm manifold details give a hg at 12,but at best i'm getting 6 on a vacuum gauge,obviously making wipers not work.
please help!:CRY:

Yeah, sounds like a vacuum leak. Check around intake and carb base. Spray carb cleaner ( be careful not to spray on distributor) around gasket areas and engine will smooth out if you find a leak. Also make sure float levels are good. That cam should have at least 10 to 12 in of vacuum at idle. I wouldn't go for the factory spredbore with that cam. The holley if working properly should be great ( except for gas milage ). Also intial timing should be at least 12 to 16.
Bill

thanks guys,i have checked all hoses several times,and run engine and checked with propane around manfold and carb,no difference in rpm,will try carb cleaner and check float levels,could leak be on internal flanges inside engine, [taken manifold off and checked all mating flanges and fitted new gaskets all ok],but i checked this by blocking breather and seeing if it sucked on my hand when covering the oil filler hole,all ok?would a pressure regulator help on fuel line,reduce pressure from 6psi to 4.5psi?

Does adjusting the idle screws on the carb make any difference in the reading on the vacuum gauge??????

dave,thanks for your reply,adjusting idle screws make slight differences,but i had to open the second [rear] chokes to allow the front blades to operate within the limits of the progression holes/slots in the carb,otherwise it floods big time! does the second chokes have progression slots as they seem to be there in the carb veturis?[no power valve fitted to rear metering block].is the holley 800 too big! as i was told it should have a 850???????

I have run engine at the weekend,trying verious things,no vacuum leaks present,but vacuum gauge reads 6/7 inches whatever with wipers etc, diss connected,tried advancing/retarding ignition,no good,could it be that the timing gears are out,as i fitted a set from paw and timed the engine striaght up,what would retarding or advancing do,would it increase vacuum either way?please help as this is starting to do my head in!