Not near as much as I expected. It feels much more peppy from 2500-4000rpm (my vtec is set to 2500rpm), but above that it feels about the same. I'm sure that is a result of being tuned to the stock cam's max potential. After tuning it, I expect the rpms to soar up to 7k much more quickly.
On the primary dyno that I've been using to tune, I'm kind of hoping for ~180whp. I still want to install the H23 IM, and 70mm TB, and get that tuned and dyno'd. When I can accomplish that, I'll call it quits on the stock block F23.