Idle tuning problems

[zach1992]

Ive been working on a 79 camaro that we ls swapped with the drivetrain from a 2004 gto. The only modifications that have been done to the motor are headers, holley single plain intake and then it has a holley throttle body. The part number for the throttle body is 534-588. The car does not have a MAF so it is speed density. The IAC that holley uses is a chrysler style. i have wired it according to holleys instructions. well i have been trying to tune idle for about a day now and im having no luck it always wants to idle around 1000 rpm. and it seems to be running lean at idle i do not have a wide band to confirm this. I talked with holley and they gave me parameters to put in to hp tuners but i do not know what tables to actually enter them in to. I have attached my current tune im working with and the info holley gave me. any help would be appreciated.


INFO FROM HOLLEY
Internal.Idle.Config.MainP= 18
Internal.Idle.Config.MainI= 32
Internal.Idle.Config.MainD= 60
Internal.Idle.Config.IACBlankingWindow= 40
Internal.Idle.Config.DBlankingWindow= 40
Internal.Idle.Config.LowsideEnablingRPM= 100
Internal.Idle.Config.LowSideP= 30
Internal.Idle.Config.LowSideI= 50
Internal.Idle.Config.LowsideD= 60

79 camaro sd 1.hpt

[Emily]

Have you wound down the idle screw to close the throttle blades??

Ensure all the vacuum ports a capped off too...

Check your IAC counts at idle with the scanner.

[mowton]

Log RPM, MAP, ECT, IAT, Advance, LTIT PN ACoff. STIT, Dynamic Air, LT and ST trims (4). IAC Steps, TPS% and TPS (v).

For starters, at operating temp, you will want to set the set screw so that IAC steps = 60-80 and the TPS (V) is lower than .9v. May take a few iterations to get this right so suggest you remove the TB and remove the setscrew from the bottom and re-install from the top...easier access.

First adjustment will be done in Park/Neutral. when done will have to repeat in Drive.

Set up a histogram that logs Idle Desired Airflow against the same temp breakpoints as in you Idle Airflow editor table (BRAF). Idle Airflow cells s/b set equal to Idle desired Airflow values logged in the histogram. This will be established in accordance with your LTIT and STIT's. Update the BRAF table with sum of the two or the Idle Desired Airflow value.

The Idle effective area table may need adjustment if the IAC characteristics are different than the GM.

Depending on the cam, timing can be anywhers from 22 degrees to 28 degrees. This is found by idling and using the VCM spark control, find the value that produces the highest vacuum (lowest Map kPa). when you find this value subtract 5 from it and this becomes your new base idle timing.

Post the logs please.

Ed M