Old thread, but I thought I'd toss out my experience for a reference.

I tried modifying a custom tune to retard timing due to detonation. I datalogged before and after altering the spark table (retarding as much as is allowed). I saw a difference of 18 to 17. It wasn't enough to stop the pinging, and I ended up having my tuner create me a new tune, but I did see changes.

hope this helps.

 

I found the problem a while back was in the tune. Since then, I went with a different tuner, and have been able to change the tunes like you are supposed to be able to.

 

When I was running my Predator it worked and mine was one of the 1st production units (was a Diablo beta tester). I know it worked when I installed the KB I couldn't wait for a full custom tune. I turned the fuel all the way up and timing all the way down for some light testing and it was deffinately different. Must depend on the custom tune you have loaded.

Eric