"New hydroformed exhaust headers route spent gases through four catalytic converters and two resonators housed inside the Viper's side sills."
The above, together with the higher compression ratio, 10.2 instead of 9.6 ( as already noted by other posters ), will be a factor in any future supercharging effort. Four cats and two resonators is alot of restriction. By the way, the GKN speed sensing limited slip differential will fit the existing Gen III's. Before you ask, I have no idea how the GKN compares to a Quaife. If anyone knows, please post.