Spark Advance Tables.... How do they work?

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Motors
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Joined: Mon Aug 23, 2021 12:56 pm

Spark Advance Tables.... How do they work?

Post by Motors »

Does anybody know exactly how the spark tables work together to arrive at a final spark advance? I'm referring to an '89 TPI Bin and $6E mask. So when looking at the Spark Advance Table I pick a certain Load Variable and RPM, then look at the intersecting cell and read the advance. Lets say it's LV8=80 and RPM= 3200. That table shows 35.89 degrees. Then there is the Spark Correction Table - LV8 vs. Temp. So same process, LV8=80 and Temp=133F and the intersecting cell says -2.46. So is it a simple calculation? Therefore, 35.89-2.46=33.43 degrees when conditions of the two tables are met? Seems reasonable to me but I need an expert.

The reason I'm asking is on another bin I see LV8=80, @ RPM=2200 is 39.0 degrees and LV8=80, @ Temp 8F is 12.0 degrees. Which would mean total advance would be 39.0+12.0=51 degrees. Admittedly this is a cold engine but I don't think I've ever seen small block Chevy advanced more than about 38 degrees... well not injected that is. Am I missing something?

Thanks!!

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