On magnesium engine cases:

The 2.7l air-cooled 911 engines were made out of cast magnesium.  This
engine kept many Porsche mechanics in work until Porsche went back to
aluminum with the 3.0l SC engines.  Shuffle pinning cases, timecerting or
helicoiling cases for pulled cylinder head bolts paid pretty well.

My '74 911 is of the magnesium alloy persuasion, completely shuffle
pinned(to keep the movement of the case edges to a minimum), timecerted
(larger solid versions of helicoils, special coefficient of thermal
expansion head bolts(to match the magnesium), 14 quart oil cooler( to
minimize the heat buildup), replaced 5 blade fan to 11 blade( to maximize
the cooling air over the barrels).  All in all a pretty poor trade,
decreased weight and polar moment of inertia for a problem prone engine.
Well once you spend a few thousand on the fixes it still is pretty fun to
drive.  But Porsche did make engine cases from a magnesium alloy.

I keep two 5# Halon extinguishers in the Porsche, the Westy and my BMW M5.
In the F150 I carry matches=;()

Helen & Joe Fahy
'87 Westy

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