I might consider the 40:1 move on the 30, but the 20, my feelings are that might not be a good plan.

First, there is no performance to be gained by the move.

Second, maybe not as much an issue anymore, but the 20's were taking out their bottom ends pretty regularly when they first came out. With the first reason in mind, and the potential for that bottom end letting go, my engines will stay on 32:1, dino or synthetic.