I have a 650-DP on top of a slightly over mild 355, and it's chokeless.

It's a Bearcat to get started, and keep running, I haven't got to getting the jets dialed in yet. Right now it's in storage, but when I had it out last summer, the idle was really inconsistent. I would set it around 1100, which was about 10" inHg of vacuum. And if you would be in the throttle and back out, it wouldn't normally go back to idle, it would be up around 1800-2000 RPM. I presume it's because the secondary's aren't adjusted right?

Engine Specs:
350 .030" over
11:1 CR (static)
9.5:1 CR (dynamic)
600"+ lift
110 LSA
(full roller)

Fuel Specs:
(stock) mechanical pump
(soon to get a Holley Black)
89 octane, might go to 91 for more timing.

If I push on the secondary butterfly lever to close it, I can get it idled down. So how do I go about adjusting that? Do I just tweak the rod?
Some input would be nice. And if you have any more questions, ask away.

Sorry, I forgot to mention. It's a Holley 6210.