Anyone have any experience with changing cams in crate?

Thanks guys.....not goin to pull the motor...maybe i didnt write my post well enough, ...I just bought the car...paid alot a cash for it....its super show car nice. It is a 4 speed car with 391 gears. It runs alright....im honestly just looking for a simple cam change, not really getting into dumping alot more money in the car. Just wondering if its possible to improve this combo with cam swap only. Thanks again