I know this is dragging up an old thread, but for info this reinz gasket is the grpA. Reinz aftermarket number for it is 61-27330-00 (the 61 is just the packaging type) and it will not be stamped with the YB number as only gaskets sold via Cosworth Technology (now MAHLE power train) have this stamp. Reinz also sell the WRC multi layer gasket (YB1429) as supplied to Cosworth - Reinz part number 61-31110-00.

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