318 Troubleshoot

Symptoms:
Starts up (usually have to hold my foot to the floor)
The choke revs her up and all's well...
She comes back down to an idle and things get kinda rocky...
It idles half decent for a little bit then sounds like its running very lumpy, as if a few cylinders flood out and eventually it shuts off.

I'm just wanting a few suggestions as to what the problem may be if you guys have any guesses... I do plan on borrowing a timing light and checking the timing. Do these symptoms sound related to being out of time?