[Gelbster]

Yes, because it is a deformable stretch bolt.
This bolt is Porsche part number 900.082.085.09
You should not use a generic grade 8 bolt of the same size:
M16 x1.5 x 60mm -but I suspect a lot of people do and just slap some loctite on it !
The correct bolt and belt (depends on specific pulley diameter)should come in the kit .

Here is an example of what we miss when the experts(not me !!) are not around:

"Tightening the crank bolt is not the issue, but if and when you go in for an IMS swap, or some repairs involving resetting the cam timing, be prepared for a significant up charge as the shop is going to have to remove the under drive pulley and reinstall a factory unit in order to lock the crank at TDC, that is assuming you have not removed too much of the pin boss from the engine cases when you installed the pulley. If you did, the trans will have to be pulled so that the engine can be locked at TDC from the flywheel. Oh, and the latter adds roughly $3K to the bill of whatever else is being done. "
Nobody mentioned this here !!!
And guess what happened when this was posted by a very well respected pro M96 mechanic - people dickered with him. And exactly the same happened when I re-posted this helpful caution. Yup - someone who clearly is not an M96 expert dickers with the wise advice - again ! And the expert patiently explains his point again to help us avoid needless expense.
My point is that without a few experts, a Forum like this is gets filled with irrelevant or uninformed 'comment'. a.k.a. -The inmates run the Asylum.