IAC too low?

[onspeed]

Cammed '00 Formula, 226/234 .598/.601 113+2 LSA (4 deg overlap), exhaust, LS6 intake, lid. At hot idle, ~200 deg ECT, my IAC count is ~10-20. I've got the set screw bottomed out (flipped for easy access, bottomed out to bolt head i.e. blade closed as much as possible). In addition I've also noticed my desired RAF is significantly lower other cammed cars, including my own Z06 which has a similar setup but with 243 heads. Lower than stock even, about 1-2 g/sec lower. I also have a weird issue where the car is slow to return to idle regardless of cracker or follower settings. With AC on and moving, it hangs at 1600 RPM for a few seconds when I disengage the clutch. Timing advance when it's hanging is what my main spark value is at 1600 rpm rather than the idle spark table, suggesting it's not going to idle conditions for a few seconds?

I'm starting to think it could be a vacuum leak? Going to pull the intake to see if anything is amiss but if someone has an idea I'm all ears.

Tune is attached, couple things need to be smoothed out but VE and MAF tables are less than 5% AFR error. On the log AC is on and you can see the idle hang at around frame 1133 using the russ k config.

edit - forgot to mention, with the set screw bottomed out my TPS voltage was still like .62v or something? I know I need it within .45-.55V so I'm guessing I'm going to have to slot my TPS screw holes?

[onspeed]

hairline crack on the bottom of the intake. applied some RTV, we'll see how things are once it cures.

[Redtruck1]

my guess tps adjustment is the key to idle hang ecm still thinks the throttle is cracked open.

[onspeed]

Adjusted TPS to 0.5V with closed throttle, IAC is ~40 hot, no change. Rechecked RAF, still about 1g/sec lower than stock across the board. Seems like everyone with a cammed car tends to need a higher RAF than stock, and are having to open up the TB at idle and lower IAC counts whereas I'm doing the exact opposite for all of that. Any chance something like a misfire or leaking header could cause this ? I notice my fuel trims are all negative with AC on.

Also noticed today when coasting with clutch engaged and 0 throttle (i.e. letting off the gas and engine braking) that bank 2 fuel trims are going very high while bank 1 stays around 0 if not a little negative. My WBO2 is on bank 1. This doesn't seem to happen at idle. I thought it might be DFCO but I'm seeing increased injector pulse as well?

Look at frame 1445 on the attached log. Was using the idle cfg for this scan, accidently deleted the one I did that logged inj pulse but it was the same. This happens AC on or off.

[mowton]

I dont know but I see the above log as stating you are running 100+ IAC count and desired air is 9.5 g/sec which is about 2 g/sec higher than stock whch isnt out of the realm for a cam like that. I would get the IAC count to about 40-60 for that cam with the set scew and then retune the Min Idle air via LT/STIT. Is it a stock throttle body?

Also .6/.7 volts s/b ok for tps volts.

Why do you have the adaptive idle enable set to 150 mph?

Ed M