I have a B18B with Crower 403s, basic bolt ons, and FPR/S-AFC... currently at 148whp/126wtq with a nice powerband. Stock valvetrain (ehh stock redline... it works).

I'm thinking about throwing in P30 pistons since they're a direct fit, to get up to 11.0 compression, up from my measly stock 9.2 now. Of course it depends on tuning and other factors, but roughly how much power and torque can I expect from this? And how much would labor cost? I definitely will do a hone/bore if necessary, car has 63k right now and runs well but I need it to last a few years reliably. Also if anyone knows of a good shop in WA (or even OR) that would be sweet.

I also have a spare LS head lying around... would it be worth getting a basic/cheap port/polish job done on it with the higher compression?