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Discussion Starter · #1 ·
I'm not saying this is right or wrong, but just did a data run on my 96 OBDII car and the timing to me looks odd.

What do you think ? I stopped at 3000 cuz it appears all advance is in.

Timing RPM
-22 854
-26 816
-28 870
-24 931
-20 1073
-20 1110
-19 1163
-19 1182
-19 1199
-19 1170
-19 1205
-19 1169
-29 1298
-31 1411
-33 1487
-34 1578
-34 1598
-35 1629
-35 1646
-35 1696
-35 1730
-36 1750
-37 1797
-37 1756
-37 1769
-37 1807
-37 1950
-38 1908
-37 1943
-38 1954
-38 2045
-38 2030
-38 2044
-39 2212
-39 2156
-39 2290
-39 2297
-40 2254
-40 2891
-40 2911
-41 2955
 

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Is your car tuned, do you think there is an issue? Looks ok to me. I can post a screenshot of a stock 96 SS timing table if you like. I'm not quite sure what your asking. Could be me, I'm really tired.

Let me know

Chris
 

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You're making a 2D table out of a 3D table in the PCM. The PCM uses 2 variables to choose the spark advance from the main SA table: RPM and MAP. Then, it uses several other scalar values, tables, and logic constraints to determine the actual SA value. And, it does this many, many times per second.
 

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Discussion Starter · #4 · (Edited)
I'm just using OBDCOM's reader to log variables and this is what i get when picking just timing and rpm.

There are 16 variables to choose from but I'm not sure what else would be of help.

Here's a link just to see what it looks like.

http://www.obdcom.com/gauges2-obd.gif


ROCCO - Post the Screen Shot ! :)

Mods in sig and PCM has been tuned twice by BH. SOP feel is good at the light, but peters out after 1/8th. Ran a 9.1 last Friday night and car "should" be in the mid to low 8's with these mods.

I'm just old school and saw the advance kick in big time at 1300 rpm, and tops out pretty much by 2200.

Just sounds odd to me.
 

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I'm not sure how long you have had your car tuned, but if you have an issue, such as fuel delivery, flatlining MAF, worn plugs (gap too big), not ideal air quality, then it will lay down. It sounds like its time to troubleshoot, or seroiusly evaluate last time major maintainance was performed. Anyway, a datalog with rpm, air and coolant temps, commanded spark reterd, knock, MAF hz or afg/s would be great.

I will post a stock table when i get home tonight.

Chris
 
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