well to answer your question, the B4C police package is not much better than a stock camaro, simply equiped with the necassary hardware the police need to do thier job. there's an event every year in michigan where they test the current/possibly future mass production patrol cars. the auto Z28 ran a 14 flat. top speed 160. but don't be fooled, the police can modify vehicles too.
don't forget texas vipers, or new mexico lamborghinis. alot of places use impounded cars for cop cars. some leave them stock, some modify them. some impound modified cars. you just never know, really.

 

in italy they have a gollardo