X-Mozilla-Keys:                                                                                 
Mike Wills wrote:

At 05:40 PM 11/2/1999 +0000, you wrote:

I think this whole situation is very instructive. It make me
appreciate the genius of Jim Griswold when he designed the
very inovative Questair Venture type motor mount. Yes he messed up
on the nose gear but he did so many other things so very
right indeed.


IMHO Jim's design is hard to beat.

Paul Lamar

  Paul,

  Can you point me at a drawing of this mount? I see a couple of detail
close up photos on your ACRE site of a Questair mount but no overall.
Should I assume that your Kis mount with hat section closely approximates
this since you believe it to be the ideal?

Yes It is as good as I can come up with presently. However I moved the
hat
section about three inches towards the firewall to get more room
under the engine for the large single radiator.

  I'm still missing something while looking at your hat section. I'm still
not seeing how it attaches to the engine. It looks like it bolts on at the
oil pan flange. If so is a custom oil pan required? If no custom oil pan
then how does it fit without interfering with the pan?

Mike Wills

It is stand alone as the stress in the hat section is mainly 
tension and that goes under the engine over to the other 
rubber mount on the other side of the engine.
There are a few holes in the top of the hat to pick up pan
bolts up near the rear rotor housing (front in AC installations). 

It requires a custom pan as it will not fit the stock pan unless
you cut a slot in the pan and weld it in. That is a cheap and 
quick way to do it. Actually I would low temp braze or silver
solder the pan to the 4130 hat section as that will minimize 
weld stress concentrations in the 4130. You mainly want to 
seal potential oil leaks. Since it is about 5 inches wide
flattened out and 0.049 thick it will accept a tension load 
of 14,700 pounds or over seven tons at a stress level of 
60,000 psi which is about the fatique limit for normalized 4130.
All this is kind of academic.

It is over designed like this to accommadate the 2.5 inch
diameter rubber motor mount bushings. Of course even in a six G 
pull up it will never see these kinds of loads. In short it is
way over designed and it only weighs 2.2 pounds. If you want to
punch a lot of big holes in the top part of the hat to save 
a little weight be my guest.

Do you need some more drawings on it?
 
Paul Lamar
 
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