You can just install them without any other work, but to get the most from them get a full cam kit. There are at least two companies that have them:
I have the Eurospeed setup which I have yet to install, both kits have m50 manifolds and ECU reprogramming.
The M50 manifold flows better then the stock intake manifold in our cars. The only downside is the loss of midend torque, which the cams do a good job of cancelling out.
I believe JazzM here on Max has/had the Eurosport/Jim Conforti cam kit in his 2.8L Z3.
That price isn't bad for the cams, but you can probably find better, I paid $300US for mine.
Also, expect to pay out the ass to get the cams installed. Like $300 or so.
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