I know this is short for camshafts right? I am curious as to what this does for the vehicle when upgraded? I am not to familiar with there complete function purpose. I am curious what this will do for my vehicle if upgraded.
I assumed you were asking regarding the car in your profile, so I moved this to the Zetec performance section for a better fit so you can find some info. that applies.
Camshafts control the intake & exh. valves, thereby the "breathing" of the engine.
Different "profiles" & timing can have advantages for different purposes, the trade-off is between max. power at high RPM vs better idle/torque at low RPM.
Changing cams can "liberate" quite a bit more power from an engine when matched with supporting changes to take advantage, "tuning" to supply the right fuel/spark to match being the most important. Intake & exh. improvements realize more gains with cams to match the increased capacity for flow.
Think of an engine as a pump, the more air you can move through it (when matched with the right amount of fuel) the more power it can produce.
They usually are worked in with other engine modifications and tuning to make better use of specific power bands as well. camshafts allow for changing the stock settings allow for longer duration for being open and also opening longer (pushing the valve further into the chamber).
They work best with adjustable cam gears and then a place to dyno tune/adjust them.