305 has pretty well hit the nail on the head.
The carb may only be slightly rich.
The overlap of your .480" lift cam will reduce manifold vacuum at idle. You want to change the power step up springs that control the primary metering rods to compensate.
Use blue step up springs. (3" ) { orange is stock} change the metering rod from the stock 7147 to a leaner cruising 7347 rod.
this rod change will not affect the WOT calibration,, just the cruise.
The cam you have needs lots of initial advance at idle.
Give it as much as it wants.
Like 20deg initial. Once you determine how much initial advance it wants at idle you can recurve your distributor to obtain this while maintaining the same 32/36deg mechanical at High speed.
This involves limiting the travel of the mechanical advance .....
Just for grins: You may even want to try locking out the mechanical advance altogether and run 32/36deg at idle and 32/36 at high speed.
Its easy to do this on an HEI. Just remove the weights and springs and tiewrap the mechanism fully advanced. Then reset the ignition timing to 32/36 at idle w/ vac adv disconnected.
ten reconnect the vac adv.
other wise use moderatly ligher than stock advance springs in the distributor or a combo of one light and one med spring.
The super lightest springs are too unstable at idle.
Then use ported vacuum advance for efficient cruising.
Take 305s advice and install a common inline fuel filter in the PCV hose . This will stop or reduce any oil from traveling throu the PCV into the manifold.
All third gen Fbodys suffer from exessive under hood heat.
Edelbrock carbs tend to be sensitive to exessive under hood heat. { "Hot soak"}this heat makes the fuel vapourize-- too well. This results in fuel perculation, vapour lock overrich idle, and fuel odour while idleing. The way to reduce this is to isulate the carb from the manifold with a wooden carb spacer. Wood is a good heat insulator.
Even a thin wood carb spacer is better than nothing.
Edelbrock sells wooden carb spacers.
Hooking up a cold air induction for your carb will help too.
www.ramairbox.com
Recurving the distributor for more initial advance or locked advance should help your car accelerate too.
Just curious,,, have you gotten a timeslip on that car?