83 K5 Blazer

I just finished converting my SBC 350 carb'd over to TBI 7747. It starts and runs but stutters when gas is initially pressed. (Problem#1) I've set the timing (removing the connector) and set to zero but it doesn't advance when connector is plugged in. When i give it gas the timing retards a few degrees under zero.
(#2) I also have a loud hissing sound like a vacuum leak but i found that the sound is coming from the top of throttle body, the hole that the IAC uses. When i stick a rag into the sound goes away and the idle goes down to normal.

Ive used the donor trucks wiring harness, sensors, TBI, and computer. I haven't installed a Wide band O2, Knock sensor or Vehicle Speed Sensor yet (waiting on money). I do have heads, cam intake manifold, and long tube headers installed. Heads I-200/E-74, Cam 206/214 @.050. I've already purchased a Burn 2, ALDL cable, Tuner Pro, and modified the ECM to accept the 27SF512 chip. (#3)I'm just at a loss when trying to figure out what i need to adjust. I basically took the ASDW $42-5.7-Manual bin and uploaded onto new chip and turned the EGR patch on. I've just been reading and trying to learn but i need the truck for driving to work in the snow. Help with any of these problems would be appreciated.

miggy

You have to shut off the engine in some years before the ECM will command timing advance again.

yeah i shut it off when i plugged and unplugged i was afraid to shocking the system. I think some how the EST is bad or went out. i have one on order.

So i changed one of the patches BPW and Spark to enabled. Got rid of the stutter and timing issue. I just have to keep reading and learning to read the log.