Strange engine case

[Peterfrans]

I bought a 7R case with crank and rods for my RS project. The strange thing is that the engine number identifies it as a 74 911 engine (6144xxx), but I cannot find an engine type number on the case. What I did find was a casting number on the case 15/79 which would mean it was produced at a much later date (week 15 1979).
On opening it up it also has the 76- oil bypass and oilpump (four ribs as in wayne's engine book). It has the new pistons, but both springs are equal length and the bottom one does not have the sleeve.
It also features the later main bearing orientation.

What could this be, perhaps a replacement case installed in the car after a rod went through the case?

I all I am very pleased with my purchase as it is in great shape and saves me some cash and machine work for the oil pump upgrade.

[Bobboloo]

Probably a replacement case that was stamped with the number of the case it replaced.

[Wayne 962]

Originally posted by Peterfrans
[B]What I did find was a casting number on the case 15/79 which would mean it was produced at a much later date (week 15 1979).

Is that true? I have never heard that before...

-Wayne

[Peterfrans]

It is puzzling me also. I thought I bought a 74 case and was prepared to do the oil pump upgrade which now is already taken care of by the factory. The other side of the case shows 19/79. I had a look at a 70 2R case I have laying around, and that one has a similar stamp without what I think is the year.

A lot of cast parts have dates on them, I see them on cylinder heads, trailing arms and even on the chain box covers.