C85 is the best hot weather fuel aside from methanol I've ever used. Makes more power than any non ox race gas too. 100 degree day and the manifold will be cold to the touch.

As for Q16 and jetting, go up, add timing and see where you wind up. VP recommended 4 sizes, on the new stuff and 6 on the reg to start. We've pulled the mains just to try to see peak before on the dyno.