If you put in the GTR cams, you also have to run all the GTR lifters and swap all the valve springs as well.
Like RB30 said....better off getting another cam that suits your engine. The GTR cams are a solid cam, whereas the GTST cams are hydraulic.
The GTR cams have a 9mm (?) lift and the GTST ones have 8.5mm
It would cost you a fortune to put in the GTR cams....picture the cost of doing a head gasket.....plus the cost of the cams, lifters, and springs. $2000 I reckon. You will get better results from bolting in a set of Tomei Pon cams and they are only $800 delivered.