to tell you the truth, one of the things that alows the gs-r to get those higher rpm's is the rod stroke ratio. it doesnt bare so much pressure on the cylinder wall. but if you do it right, the ls combo in there with a crazy compression like 12.0:1 or something like that will make that motor scream. But say you setup was stage three cams (your choice of good brand) new valve springs and retainers. Then you get that high comp with the ls stroke in it, thats a very potent motor.