Correct me if I'm wrong, but the purpose of using an LS block for the ls/vtec setup is because the ls has a longer stroke than vtec blocks. Now, I think it was insypral who taught me this, but what seems best to me is to use a GSR block and put in LS crank and rods for the longer stroke. By doing this, you dont have to do all the machine work on the LS block to make it safe for high revving.

I like ls/vtec a lot. A guy I met at the street races with ls block and a b16 head with all the goodies was claiming somewhere near 250 hp (I dont remember his exact number). His car was pretty damn quick...