Engine case quandry: 4R left, 3R right, is my motor a bastard?

[jim72911t]

Hi all,

Tonight, while getting my case ready to take to the machine shop, I noticed that I have a 4R left side and a 3R right side. Specifically, the part numbers are: 901.101.101.4R (left side), and 901.101.102.3R (right side).

Is this unusual? The car is a 1972 911T with MFI. Should I look for a replacement case with matching series numbers? I thought I read somewhere that some cases have different series numbers from left to right, but can't find the thread.

I'm a little worried that the car might be more of a bastard than I originally thought. Should I be concerned?

Thanks,
Jim
'72 911T

[Wayne 962]

No, this is quite typical for your engine. I think I mention this in the book? Not sure. Don't ask me why - I think that Porsche added something to the casting on the left side while still using the same right side.

-Wayne

[jim72911t]

Thanks Wayne,

I've been looking through your book for an hour now but didn't see it. Might have missed it. Thanks for the quick response.

Jim