IAC Count With FAST 307603 Throttle Body

[2xLS1]

I have a combination I'm trying to sort out that I've never seen before. It is a 00 Truck with a 5.3L Small Lunati 220/222 cam, LT Headers, a Victor Jr intake and this FAST 307603 Throttle Body.

Uploaded with ImageShack.us The problem is with the IAC counts in P/N vs in gear. The truck does have a stock converter. Target idle speed is 715 P/N and 685 in gear. With the Throttle Body stop screw backed all the way out the IAC's fluctuate between 0 and 10. As soon as you put it in gear the IACs slowly climb until they hit 310 and stop, Then the idle slowly starts dropping to around 400 rpm. I can't open the blades any to get the IAC's down in gear without the counts going to 0 in P/N. This is the first time I've tuned anything with this throttle body and not sure what the solution is. The customer says he has read where people using this TB just unplug the IAC and just set the idle with the set screw. Seems like that would cause a high idle in P/N and while cruising. I would much rather find a way for the IAC to control the idle.

[12secSS]

The "Area vs Airflow" is different from the stock IAC on this throttle body's IAC, and you will need to generate a completely new "IAC Counts vs Airflow" table for the PCM to properly actuate this new IAC. Those that say "just unplug it and set idle via the set screw" choose the easy way out. Mind you, to set it up properly will require a lot of data that maybe very hard to source. The IAC Steps vs Airflow, which tells the PCM how much airflow goes thru the orifice at a given step will be the hardest.

[2xLS1]

It is the large spread between P/N and in gear that has me stumped. 10 to 310. It seems that anything I do to bring down the counts in gear even if the IAC Steps vs Airflow does is just going to drive the P/N to 0 since it is so close to that now. So gaining control in gear may just make me lose what control I have now in P/N. I was hoping someone has tuned something with this TB that has figured something out. I believe it has been around for a while.