I woke up this morning with a bright idea.
Why not use square telescopic aluminum tubing as a cross
tube to take the engine loads in the motor mount?

Damps out any weird vibratory modes that might develop
and will increase the bending strength of the cross tube.
So here it is. Probably easier to fabricate than the
Questair type of two inch steel tube and 3/4 inch thick
aluminum plate. Tube Sales, or what ever they are 
called now carry 3 and 2.5 inch square 1/4 wall 
aluminum extruded tubing.

http://WWW.twmetals.com/

Btw I calculated the stress in the pan wall for a 9 G
pull up load with this 3 inch square tubing welded
in. It was only 7300 PSI. Well within the capabilites
of the welded aluminum pan without the doubler shown.
The doubler adds minimal additional weight  so you can
weld it in if you like.


If you want to reduce the weight you can cut a bunch of
1.5 inch holes in the vertical walls of both inner
and outer tubes. Don't do this within the pan on
the outer tube to maintain a sealed pan.
This will look trick and impress casual observer :-)

Paul Lamar        sqrpanmm.gif
 
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