What crank is this?

Sorry;
All my catalogues (even discontinued parts) and all my internet show nothing.

Closest I could find is P4452978 (billet 360 race) with 3.58” stroke and says the “actual main journal size is 2.8095-2.8105”. does not specify 6 or 8 bolt.

340 mains, 8 bolt, 3.58 stroke?

Nice crank but what the heck is it !?

Where did you get this rare mysterious piece!?
:popcorn: