I baaaaarrreeeely understand cams when it comes to vehicles. I know what they do, I know you can get different ones. But what's the difference? Are they able to add HP? Torque? What do they mean by an aggressive cam? What are the downsides of getting a more aggressive cam? Do they have a big influence of the rumble guys like me like to hear trucks (and muscle cars) have? Anyone care to share their thoughts, ideas, and comments on the subject? If you get too technical my eyes will glaze over. Any chance you dumb it down for me? Thanks in advance!