When did engine assembly bolts change?
 

I'm trying to figure out when my replacement engine was remanufactured by Porsche. It started life as a 2000 2.7. It was a factory reman, with the post '05 (?) IMS. Comparing it to my old engine it has 12 point engine fasteners instead of 10mm head hex. Takes a different kind of socket.

When did Porsche change the engine fasteners? Most all of the case bolts, valve cover bolts, even the bolts for the alternator are different from my 2001 engine carcass. Once one has the socket set (available at Harbor Freight for almost nothing) I like these fasteners. Socket fit means that engagement is very solid.

Over the years, Porsche has gone back and forth on six and twelve point fasteners at various locations on the engine and the body of these cars. At one time, they used metric torx style flywheel bolts instead of Allan head fasteners. Never an explanation of why, it just what they do.........