Aluminum or magnesium?

[GraybeardsGhost]

Need some info...I'm trying to determine if my case and tranny are magnesium or aluminum.
I've done the metal shavings test off both, plus a true aluminum piece for comparison. All tests with a torch result in glowing metal shavings but no fire (magnesium is supposed to burn, right?)
Here's the parts numbers...case 901 101 102 OR , stamped 901/17 10584
and the trans 901 301 101 OR
Thanks again.

[Zeke]

Oh boy, I wish I coudl tell you by the numbers alone. I could go look in my red book and probably figure it out. The reason I'm replying is that any alum cases I've had clean up bright and shiney with a number of household cleaners. Not so with mag. Dull gray no matter what you do. Many people paint it. I got a mag tranny nice by pouring acid over it. Not recommended, but it works. It'll ruin a gasket surface in seconds.

[fintstone]

Well 901/17 is a U.S. '68 number...for a sporto engine, and my understanding is that the "68 model year used only mag cases.

[Fishcop]

Flinstone is right on the 1968 vintage and the sporto, but 1968 crank-cases were aluminium, the change to magnesium occured in 1969. You will know magnesium when it burns... not just a spark, but a true "flare" as it burns. I believe that you have an aluminium engine.

[Doug Steinel]

refer to Wayne's engine book, pg. 48.

[fintstone]

Interesting! The B. Anderson book says that the case change to magnesium was spring of '68. Guess Wayne trumps BA!

[GraybeardsGhost]

Thanks for all the help. For reference purpose, the true build date of the car/engine was '67, build #11830165.
Is there a market for early 2.0 cylinders, pistons, and heads that are in great shape (no internal/external damage)? I'm planning on upgrading to 2.7's.