Ummm, what?. Of course they have cam gears (you yourself just called them sprockets, same thing). As far as camshaft turning and timing etc is concerned there is no difference between timing chain and timing belt, just one is made from rubber (and has a habit of stretching and breaking if you don't change them at set intervals) and the other from metal (which doesn't stretch as much and generally lasts the life of the car). You're more likely to come across problems regarding cam gears when it comes to implementing the VVTLi, which not all aftermarket cam gears would be capable of replicating. I assumed he was thinking of aftermarket adjustable cam gears. Nothing available for that AFAIK for the 2ZZ, not like you would need it anyways. My head and my fingers weren't in sync <_<