What determines ball joint version?
 

I see from searching the archives and Pelican's catalog that there are two types of front ball joints. There is the kind that uses a bolt (used through '71) and the kind that uses the pin ('72 and later).

My question is: what other part defines which one to use? Is it the strut? So if I have a late strut, I need to use the pin-type?

Or can either type be used with any 911 strut?

Hmm, anyone? :)

Darren from Pelican comes through with the answer!

"It would be dependent upon whether or not your struts are held onto the ball joints by a M10 x 30mm through bolt, or if they are held in place with a threaded pin. The early struts had a slot cut into them that was compressed with this M10 x 30mm bolt.

The threaded pin will have a blunt end on the one side and a nut on the other. The threaded pin is kind of shaped like this ( > , where one side has a nice radius and the other has an angle which fits into the slot within the ball joint. These wedge shapped pins were used with the later struts which didn't come with a clamping slot cut into them.

So it would be dependent upon which struts you are running that would decide as to which ball joints you would need. If your car has the hydromatic front struts, there may be some other issues."