A beautiful matching set (p/n 911.104.303.OR - Casting Date 03/70) of six 911 S/T Factory Racing Twin-Plug Heads that I sold September 2005 to an ST owner. These racing heads reportedly came from Ritchie Ginther (modified and flowed by Bill Yates, his engine builder). A copy of the engine dyno-sheet from Bill Yates came with these ST heads.

As you can see by the photos, I had the heads restored and they now look perfect with new valves, seats, springs and Titanium retainers installed. What I find truly remarkable is seeing how these ST racing heads survived all these years with no broken cooling fins, or any other obvious chamber area damage.