So far not a lot.
All I've done so far is twist the guts out of the secondary, 9/3 on the stock spring and their helix. And ground some weight off the tip of the daltons they sent.
I will keep adjusting until it perfect but the way it is, it back shifts solid and holds rpm, but still is giving up some up shift in the mid range, and not shifting out all the way.
This is at about the 8-9000' range.
I think it needs more finish on the helix, and a stiffer secondary spring with less twist...
But again as is, it rips. Just leaves a little left for me to try for!