[Bobboloo]

Your correct Bob. 901-101-101-7R and 901-101-102-7R are the castings numbers for the left and right side of the case.

As for the arcticle from Porsche 911 World they are in error not only about the 7R cases but also about the 2.2L engines being the first mag case engines. The first mag case engines were made in 68' which were 2.0L engines. The 2.2L ones didn't come out for another 2 years.

The way the article reads it seems to suggest that 101-7R was a 2.4L case and when they went to 2.7L the case was then numbered 102-7R. In fact the castings numbers are the same for 2.4 and 2.7L 7R cases. The machining is what is different in that the 2.7 cases had larger spigots cut into them.