1977 Porsche 911S 2.7L Mystery Motor Question

[FxAffPro]

Hi All,

I am a newbie to Porsche cars, and recently came into a 1977 Porsche 911S with numbers matching Engine/Tranny. I have a question if anybody can give me a clear answer:

I know that at some point in time that the engine was rebuilt, as to what extent that means I do not know. Unfortunately I have no service records or any kind of documentation on the car other than knowing that the car has sat for 18 years.

On the Right Side of the Crankcase the Casting Number Reads: 901.101.102.7R

On the Left Side of the Crankcase the Casting Number Reads: 901.101.101.7R

On both the Right and Left Side I believe the "Cam Housings/Towers" Casting Numbers Read: 901.105.111.1R

Is this common that these numbers do not match? Is one number for the Right Side and Left Side of the Crankcase "Like Piece #1 and Piece #2"? Is this the 901.101.102.7R Case that Bruce Anderson talks about in his Performance Handbook?

I have been obsessed with this car and love it, I want to learn and know everything I can about it.

Any insight anyone can give me on this would be greatly appreciated!

Thanks!

[kenikh]

Totally normal. Those numbers never match. They're casting numbers, not serial numbers.

[FxAffPro]

Hi Kenikh Thanks! Do you know if this is the same 901.101.102.7R Magnesium Crankcase that Bruce Anderson talks about in his Performance Handbook?

Thanks Again!

[kenikh]

7R cases were made from late '72 thru mid-77. But yes, they are generally all the same, at least structurally.

[FxAffPro]

Thanks Kenik I greatly appreciate your responses on this!