By down low I mean I had my timing at 28 degress across the entire rpm band. Then, I used the IATvsMAP table to take timing out. The hotter the blower and air got the less timing I had. Although I never went down the 1/4 mile, on the street after 8 to 12 second bursts of speed my timing would be at around 20* to 18*.
It worked perfect. The fuel might be alittle different where you are so I would start at 22* as a base and then work your way up. I tuned and tuned on my truck until I had it perfect. Of course my A/F ratio was a safe 11.3 and then leaned out to 11.8 at 6,200. If you are running leaner it will make a difference on the timing.
Good luck.


Edit: I had a 6.0 which has less compression than a 5.3 so your timing will be alittle lower.

 

I see. I'm looking at logs right now, and it looks like the only time I get detonation on 15 degrees is above 110 degrees IAT. So I'll go ahead and use that for a starting point. Say 22 across the board, then take timing out of IAT MAP gradually until I get to 7 degrees by 110 degrees IAT. (110 is the end of 1/4 mile run with 60 degree outside temps)

We are stuck with 91 octane premium here. My AF is steady at 12 to 1.

Thanks alot man, I never thought to use that table that way. I zeroed it because of inconsistant timing when I first started tuning . It confused me.
Now that I'm getting better, I understand it more. That should really help!

Sorry I kinda highjacked this Parish. At least its still on the topic of timing.