Help decoding a engine number
 

I assumed my 1975 911S had the original motor in it, but now I'm not so sure. I'm hoping one of the forum guru's can double check this number for me. I have this number stamped on my engine block, 6106197. According to what I've found here on the forum that makes it a 1970 911T motor, I'm I correct. If it is, is this a good thing or bad? As in will it affect the value of the car? I have receipts showing a complete engine rebuild including new Pistons and cylinders. Could it be the shop use an older block and made into a 2.7 liter? This shop is long gone, but I did find mention of it on the forum, so I believed they did quality work.

Any help old be greatly appreciated.

Thanks, Bruce

Yes, it could be a 1970 engine, especially if the type # is 911/07. Not likely to be a 1980 engine although the year digit is the same; but type is 930/xx.
Yes, the block could have been re-purposed if too much damage occurred with the original block in the car.

Thank you very much djpateman. Looks like I need to do more investigating. Do you believe this motor would affect the value of my car?

Yes, I think it would lower the value simply by not being matching numbers. Also it may be a slightly less robust case than the original. But a lot of the loss in value depends strongly on the condition of the car.