Does Supra RZ Mach 4 have more power than the R34 Nissan Skyline GT-R? If so, by how much and what is the torque difference?

Mark 4 = MKIV, it's not a gillette rasor. You're going to have to be more specific if you want a real answer, some lower production GT-R's have more hp, some normal versions have less. Google is your friend, put some effort into it.