Yes I have the stock iron heads, and yes the stock cam is mild.I found a Spark Advance vs Rpm vs Load Table example in a forum for a 1985 C4 TPI like mine. The post said it would ping in over 80 deg air temp but he could race at lower temps with 95+ octane gas. He mentions 10:1 compression and distributor timing is 4 deg, but I see it as an example of the absolute max advance values. I think that his retarding the distributor timing by two degrees forces the ECU to add an extra 2 degrees to the final, not sure about that. Using a spreadsheet, I calculated the cell by cell delta values for the my stock map vs the max map. Then I added 1/4 of the delta to each corresponding cell to create a work Spark Advance vs Rpm vs Load Table. For example, if the max table was adding 8 degree over stock, I added 2. For 3200 rpm X 144 load the stock value is 34.10 while the max value is 42.90. So that would be a stock advance of 6 deg + 34.10 deg = 40.10 deg spark advance. The new advance would be 6 deg + 34.10 deg + 2.2 deg = 36.3. Not a big difference but I was being conservative for my first spark map change. I datalogged a few 2nd/3rd gear full throttle runs to 5000 rpm, and didn't notice a difference in my butt-meter. The most important thing I was testing was to see if the knock flag had been set in any of the data points in my logging. I didn't see any. I have seen other error flags get set in my datalogging so I have some confidence that the knock flag will show up as a warning. So I was adding 1-3 deg of advance across the table and nothing happened. Anybody surprised? Why won't this thing let me do line breaks?