Wheel option list
 

Spent some time researching part numbers. Going to leave this here for reference. If you have any additions, deletions, or corrections please leave them here.

wheels (17 x 8.5 only):
twists (996 Carrera 2) - 996.362.126.05 50mm offset (67251)
twists (Boxster S) - 986.362.126.05 50mm offset
semi twists - 986.362.126.06 48mm offset (67259)
5 double-spokes (Boxster II S) - 986.362.126.07 48mm offset
BBS - Sport Classic XRA - 993.362.126.55 50mm offset (67239)

There's a good, but incomplete list of wheel offset, part number, and weight info here:
944racing

Yep that was one of my references, but it was missing many of the part numbers and did not indicate wheels legal for Spec Boxster.

Your list seems pretty complete Todd. Per the 2016 PCA Rulebook for SPB;

"I. Any factory cast aluminum rims intended for a Boxster and matching the original offset are allowed; front wheels must be at least 18.5 lbs. and rear wheels at least 20 lbs. Rear wheels must be 17 x 8.5 inch, 48-50 mm offset. Front wheels may be either 17 x 7 inch, 55 mm offset, or the same size and offset as the rear wheels (17 x 8.5 inch, 48-50 mm offset)"

This statement has always bothered me and makes me wonder if someone could question whether 993 or 996 wheels were "intended for a Boxster"?

How is anyone to know the real "intent"? Whose intent? When? Based on what?

It's easy in PCA, you call Susan Shire with the question and she will have Walt tell you no. :D

Actually, the size parameters in the rule book limit the OEM Porsche factory wheel fitment to the wheels Todd lists, basically 8.5"x17"x (48-50)mm offset. Not many use the 7" wheels up front, if any.

You had me laughing out loud! :D

I wondered about the "intended" as well when I was putting the list together. Seems a little vague; putting the part numbers allowed in the rulebook would eliminate a lot of questions. And this is coming from the guy who makes Spec Miata rules for SCCA!

I take it to mean any Porsche OEM wheel in 8.5" width and 48-50mm offset that meets the weight parameters, and I believe any wheel made by Porsche that meets these requirements is legal.

So these BBS - Sport Classic XRA - 993.362.126.55 50mm offset (67239) meet the minimum weight requirements? The 944 racing site lists the 17x9's as weighing 21.12 lbs, therefore the 17x8.5's must be lighter and close the the limit?