Slow89Iroc-Z

Car has mods in sig......I was running the AUJP spark table as well as the AXCR table..no change....blms are at 128 in that area....I have no egr....and no knock...why the unsteady cruise? I have the map sensor installed like the factory V6 cars mounted on the firewall with a nylon line feeding it vacuum... Can it be the LT4 hot cam, heads, stealth ram...lack of egr???
Thanks!

Grumpy

Cut and paste your timing table.
You should be able to get the motor happy.
Are you able to data log?.

Slow89Iroc-Z

Main Spark Advance Vs. RPM Vs. Load

_RPM___________________MAP (Kpa)
_____20__30__40__50___60__70___75__80__85__90__95__100
_400 20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0
_600 20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0
_800 20.0 20.0 23.9 23.9 23.9 23.9 22.9 22.1 21.1 20.0 20.0 20.0
1000 20.0 22.9 26.0 26.0 26.0 23.9 22.9 21.8 21.1 20.0 20.0 20.0
1200 20.0 25.0 28.1 28.1 28.1 26.0 25.0 23.9 22.9 22.1 21.1 20.0
1400 20.0 25.0 32.0 32.0 32.0 20.4 20.4 20.4 20.4 20.0 23.2 23.2
1600 25.0 30.2 30.2 30.2 23.6 20.4 20.4 20.4 20.4 21.1 26.0 26.0
1800 29.9 30.2 30.2 30.2 25.7 20.4 20.4 20.4 20.4 23.9 26.0 26.0
2000 29.9 30.2 30.2 30.2 27.4 30.6 29.5 27.4 24.6 23.9 29.2 29.2
2200 29.9 30.2 30.2 30.2 27.4 34.8 30.9 28.1 25.0 22.9 30.2 30.2
2400 29.9 34.1 38.0 35.9 35.9 32.0 28.8 28.1 26.0 22.1 30.6 30.6
2800 29.9 34.1 38.0 34.8 34.8 29.9 27.1 25.0 23.9 21.1 30.9 30.9
3200 29.9 34.1 38.0 34.1 34.1 27.1 23.9 22.9 21.1 21.8 31.3 31.3
3600 29.9 34.1 38.0 38.0 34.1 28.1 26.0 23.9 22.1 22.1 32.0 32.0
4000 29.9 35.2 40.1 40.1 34.1 28.1 28.1 26.0 22.1 22.1 32.7 32.7
4400 38.0 40.1 40.1 40.1 40.1 33.0 30.9 28.1 26.0 23.9 34.5 34.5
4800 38.0 40.1 40.1 40.1 40.1 35.9 32.0 29.9 28.1 26.0 36.2 36.2

Twilightoptics

What about hwy fuel mode?

At 55-60 mph... 1500-2000 rpm I have a stumble too. If I hold that speed/rpm for a while the car will start to hesitate and slow and kinda feel like it's not getting anything. If I don't move my foot from the same spot on the pedal, I'll get a SES light for MAF and if I give it gas or slow down the SES light will go out and I can keep driving till it happens again.

65+mph and it doesn't do it even just cruising at 65 it wont do it. Just between 55-60 and my HWY FUEL is set at 55mph...

?

Grumpy

Try something like this.
Your WOT high RPM timing looked a lil high so I brought it down a few degrees.
If you don't NEED the timing up on top you'll do better without it, long term.