C14NZ engine tuning

Moin, I wanted to know what you can do with the C14NZ and how much it costs and what it does (in terms of performance)? I also read somewhere that you can install cylinder heads from the C16SE or something like that, what fits on/to the engine block (inlet bridges, exhaust manifolds, etc.) and what does that bring? Since I already have the engine there, I want to install it, so no C16NZ or something to install it. … know a side where there is a instruction to change camshafts, manyleic ht equals the C14NZ (possibly with pictures).