GS? Do you mean GSR? Does it say DOHC VTEC on the valve cover? If it does, you're looking at a horsepower increase of 40 HP @ 1600 higher up the power band, and a torque increase of 6ft-lb @ 1200 rpm higher up the power band.

Total output for horsepower is 170 @ 7600 and torque is 128 @ 6200. Oh, and not to mention that if it is the GSR engine (It should say B18C1 stamped on the front of the block, next to the transmission), then that's a very high in demand engine.