By "Z-cam" are you talking specifically about Elite's Z cam or are you referring to cams in general? Both a wheel and a cam on a bow are eccentrics. The cam is different in that it accentuates where and how the force of the draw peaks during the rotation of the eccentric in order to store and deliver more energy than just a round "wheel" can. This can be shown graphically by looking at the force draw curves of any two different eccentrics. Norb Mulaney's Bow Reports are a great place to view comparisons about how a specific bow's cam performs through it's draw cycle. Generally speaking wheels are going to be smoother to draw, store less energy (and therefore be slower) and they'll likely be more forgiving than a cam. The Z-Cam has a profile that allows it to be ultra smooth yet still perform well in relation to storing and delivering a high percentage of energy. It's a good hunting and target cam as a compromise between a radical, hard speed cam and a round wheel.
