[alffie]

The LS7 is a "gen 4" The new 6.2ltr LS3/LS9 have the LS7 heads and manifold. The LS7 heads will fit on the LS2 blocks but have 2.2inch intake valves that will have clearance issues with a 4inch bore, will depend cam lift etc. If you use the LS7 heads you will need the LS7 manifold. Alt,starter etc are the same on the LS7/2.