the LS2 has the 3.9" bore and a bigger stroke. thats why a VE SS with the L98 would woop a VE HSV LS2's butt. hence why hsv did i mid series facelift with the introduction LS3 because it was embarassing. The LS2 uses the same head design as the LS1, casting number 241 for ls1 and 243 for the ls2. the LS2 had some minor changes porting etc to increase flow, but was not enough to match the flow figures of the L98 superior heads.
Walesy- how many times in the last few weeks since i brought this to your attention have heaps of "experts" been wrong.
The LS2 heads will offer small power gains but nothing compared to a CNC ported polished set of aftermarket heads. if you can get them for under $500 it would be a worthwhile upgrade, get the faces machined 30thou, usually costs about $120 from most machinest. the slightly increased flow and raised compression will waken up a mild cam.