A trip down the drag strip will tell the tale of how much HP you are making now.
Based on the 1/4 mile MPH and vehicle weight+driver.
i would get myself a way of listening-detecting for detonation under boost.
Further boost testing should be done with high octane gas. Then water methanol injection.
The fuel curve and timing curve will be uber critical as well as the fuel quality (octane).
There are many good water meth injections systems on the market now.
a google search will show you.
Personally if you are making 9+PSI I would stay right there.
Consider adding the water meth inj now at 9PSI to allow needing less timng retard under boost
It will make more power.
Further gains will not be that much more power per #of boost.
Mother nature takes care of those that get greedy with boost on pump gas.
The Darwin effect.
Why not get some 110+ unleaded race gas and try the 12# pulley, then get that out of your system and put it back to
a workable, reliable 9psi with waterinjection and boost retard as required.
The cam can be improved for more power at 9psi too.