Don Dunbar wrote:

Hi Paul,
It has been some time since my last communication, I have been busy with work and have put in many hour to complete my engine mounts.
I have followed the news letter on Finn's problems and have my own opion to the end result.
I have attached photos of my mount construction for all to view and comment.
The rubber bushing's that I have used have a higher operating temp than the Barry natual rubber mounts.

I believe that Finns problems with his mounts are as per what you have said that they are not designed to be used in the method he has used
them.

There are manufactures guidlines for the tension and compresion for these mounts and with heat and the method that Finn has used them
will generate more heat and wear the bushing out fast.
There are other bushings availiable with a range of operating temp's from 80c to 200c, this is the operating temp's not the melting piont of the
bushings.
Regards Don Dunbar

Looks good Don. Looks like you picked up more than just six pan bolts.
How many were you able to pick up? I assume it clears the stock
91 turbo.

Barry does not make natural rubber anymore as far as I can tell.
Natural rubber is still used in a lot of conical aircraft motor mounts
that I have seen. Natural rubber is 180 F. Barry now uses neoprene
which has a temp limit of 200 F. Barry can supply silicone on
special order with a temp limit of 500 F. Chuck Dunlap made
his own rubber mounts using cut washers out of silicone sheet
rubber glued together with red RTV. How are they working Chuck?

Paul Lamar
 
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