The 225/50-15 - 285/50-15 P7 combination may have only been OEM on European GTS Panteras manufactured after the P7 became available but that size combination fits the thousands of regular L and pre-L Panteras made between '71 and '74. Some will say a 285/50-15 is a bit wide for the Pantera's 8" OEM wheel but it was within Pirelli's range of approved wheel widths. Furthermore, hundreds of owners have fitted the OEM 10" rear wheels which are perfect for the 285/50-15. None of this will be news to Pirelli, assuming they still have records of how many 285/50-15 P7's they sold while it was in production. They certainly would have sold more than 100 pairs of tires! Keep in mind, there were VR speed rated alternatives back then, including the 275/55-15 P7. Today, in a matched set, there are none.