The LS7 is a small block 427. I think it literally uses the same block as the LS1, but with obviously a bigger bore. 455 is putting better numbers to the ground than stock Z06's, and the Camaro engineers claim it makes less power. Someone is lying here, and I think it's the Camaro engineers. I doubt Ford will aim at the Z/28, primarily because it's pretty much the parting piece of the 5th generation. GM has finally cut the ties off of the Camaro engineers and are letting them make them as good as they want. So I think the 6th gen v whatever gen Mustang it is now battle will be pretty epic for everyone from both sides.