Well it is basically the design of the LS9 with many different characteristics...it is still all aluminum 6.2 with the Eaton Blower...granted the Vette has a 2.3 vs. the Caddy's 1.9 or something like that. Boost is lower on the Caddy...its under 10psi. Intercooled differently...pistons arent forged...ummm...oh and the Caddy has a 3 belt system vs. the ZR1's typical twin belt setup like on a GTP for instance...miss anything?