Can't get it to idle right!

Hey all, I've been trying to get my project car sorted out, one of the problems I'm having is that after I get the engine warmed up the idle will jump all over the place!

Here's what I got:

It's a 340 with J heads, RPM intake, an Edelbrock 750, and stock electronic ignition with a vacuum advance.

I don't know much about the motor. I got a great deal on it, it runs great (when not at idling) and it has good oil pressure and compression.

The previous owner told me it has hydraulic cam (it has a pretty good lick to it and driving down the road it really wakes up at around 3K rpm), and it also has a high stall converter.

I set the timing to 30 total advance @ about 2K rpm. all I could figure is that distributor might have issue, or maybe the vacuum advance may be the culprit?

I have never have dealt with a motor this wild before and I could use some advice.:D