GSR cams are very slightly hotter than b16 cams. If I remember right they have 3 degrees longer duration or somesuch. If you're really bored you can install them, but I'd be surprised if you got more than 2 hp out of it.
If you're going to spend money to upgrade your cams, I'd skip ITR and go to Skunk2 stage 1 cams. They've always shown really nice gains on b16s and you can use your stock springs so long as you don't rev over stock redline.