There were some major issues with the aluminum cases on occasion.
I won't elaborate but here is a thread from the Samba that addresses some of them.
Aluminum vs. Magnesium
Personally I like a mag. case up to about 84-86 stroke then the bubbletop aluminum case is much easier to make the big strokes fit.
CB Performance raised deck versions are the schnitz for those.
They have some quality control whereas some of the other vendors let just about anything get out the door.
Here is a picture of just that:
This case had a casting hole into the head stud.
Sorry about the poor quality picture.
Mag cases are die forged, the aluminum case is sand cast.
Draw your own conclusions.........

_________________
Gary
Turbo VW Sand Racer
Polaris Ranger
"If you don't run into the Devil every once in awhile, you must be going in the same direction!"
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