a stock gsr with jsrc at stock boost (6psi) should see about 200 whp, example
http://jacksonracing.com/CustomerSer...ntegragsr2.gif
200 wheel could get you into the 13's if you drive well.
but it would also make the car hella more fun to drive with all the extra tq. and stepping up to more boost is just a pulley and a belt away. i would recommend adding hondata though.
addtl boost doesn't get much peak gains, but will def deliver more low and mid-range tq.