Very surprised that over rev situations that result in a knock light aren’t discussed in this thread.
2 of us with MaxSpool 16 3 bar tunes, get those double red lights when playing with clutching or different belts causing over revs. Get the revs back down to the higher limits we like and no knock light even with 90 non ethanol.
I like mine at 8950-9050.
That’s when the Max rpm comes in handy, even if I only see, say 9150 or so, if I check my max rpm it may have seen a quick event of 9450-9650, so rev limiter engaged I think.
Have swapped from the 8JP to the 825 this season, and so also trying different clutching.
If I leave my 35-39 reverse helix twist at 6-1, which is where I was at with the 8JP, revs are all over. From 8400- 8800 back and forth, but no knock light. Crank that twist to 6-2 and there she is, right back to where I like it, but maybe a knock light on long WOT stretches, but mostly no. Have seen two so far this season.
My buddies sled is the same, even though he added a header this season, or no knock light until clutching for higher revs.
So if we were to clutch for stock 8750 revs, no lights would be seen! But dam those 998’s go and sound so good with higher revs!