from the OP name, its probably a 1988-91 civic Si and not the 99-00 EM1 Si since it was not clarified enough, and it prob. just has the B17 GSR swap in it.

Buy a bigger TB also when buying a IM cause getting a aftermarket IM and not having the throttle bodie same size is plain useless,

66mm TB, Skunk2 IM, PRO1 cams, RMF rep headers, and a dyno tune, those 4 bolt-ons will make a big difference if the motor is healthy.