Need help with at speed off throttle hunt

[KAZ MotorSports]

The car:

2000 T/A LS1
224 / 224 588 588 112LS Cam
LS6 heads ported
long tubes
3500RPM stall / 3.73 gears
80mm TB
granitelli 8xmm MAF
LS6 intake
more I am sure that I am not listing, but most likely not all that important.

The car pulls a 12.8 @ 110 in the 1/4 (at 5800' above sea-level) and runs perfect except for one thing.

When the car is being driven (yes also a daily driver) the RPM will fluctuate between 700 and 1050-ish when no load is on the car and it is coasting in gear. The slower the speed of the car (say 15MPH to 30MPH) the more it shows it's ugly head. The faster the car is traveling (approx 45-ish to above 50) it is not noticable or not even there. I have corrected just about everything airflow and overspeed/underspeed possible that I have in my notes and from Jeff (thanks dude!). I do not want to say what I have changed in order to get some fresh eyes on this issue.

PLEASE post what you would have changed in your customer or personal setups to correct this. I will confirm if I have already done that or not. If what you suggest works I will post it up for sure.

Thanks so much guys!!
-Kenny

[SSpdDmon]

The car:

2000 T/A LS1
224 / 224 588 588 112LS Cam
LS6 heads ported
long tubes
3500RPM stall / 3.73 gears
80mm TB
granitelli 8xmm MAF
LS6 intake
more I am sure that I am not listing, but most likely not all that important.

The car pulls a 12.8 @ 110 in the 1/4 (at 5800' above sea-level) and runs perfect except for one thing.

When the car is being driven (yes also a daily driver) the RPM will fluctuate between 700 and 1050-ish when no load is on the car and it is coasting in gear. The slower the speed of the car (say 15MPH to 30MPH) the more it shows it's ugly head. The faster the car is traveling (approx 45-ish to above 50) it is not noticable or not even there. I have corrected just about everything airflow and overspeed/underspeed possible that I have in my notes and from Jeff (thanks dude!). I do not want to say what I have changed in order to get some fresh eyes on this issue.

PLEASE post what you would have changed in your customer or personal setups to correct this. I will confirm if I have already done that or not. If what you suggest works I will post it up for sure.

Thanks so much guys!!
-Kenny

Kenny,

You mind emailing me his tune? I'm curious to see what's what.

[KAZ MotorSports]

Jeff,

PM me your email address. I have it on the home office computer...not where I am now.

Thanks,
-Kenny

[Doc]

Sounds like there might be a descrepancy btw the spark tables; idle, High/Low at light load/ rpm values. MAP the spark and I think you'll find your bad actor(s).