I have (4) "stock" cams. They all have "BMW" on them. 2 of them (from my '88) have serial? numbers 0262 & 0269 and the other 2 have serial? numbers 8??9 & 8299. The last 2 also have "400" on them? All four of them have a number stamped on the "gear" end. I have no idea what these mean.