RE: trailing arm bolts

[Darryl Tinnerstet <darryl@xxxx>]

Toby said:
> However, if the trailing
> arm bolt fails, the joint is completely lost. There is no redundancy,
> no alternate load path. A critical component with no back up, whose
> loss could result in catastrophic loss of control or major damage to
> the car.
As I noted earlier, I find it interesting that Chevrolet (where we all know
John D. used to be employed) solved this problem on the Corvette way back in
1963 by putting the rubber bushing in the end of the trailing arm and
supporting the bolt at both ends. The bolt was not subject to flexing, and
if the bushing wore out or failed it was still held in place by the arm and
bracket. So why did DMC/Lotus do it the way they did? We will probably
never know. But we do know that the stock bolts, and any of the previously
available replacements, are the weak point of this design. Like the fan
fail relays, window motors, angle drives, and door struts, its not a
question of IF they will fail but WHEN they will. But the others seldom
have catastrophic results.

I think we need to accept the expertise, research, and engineering Toby
brings to this subject, compared to the suggestions of some with
significantly less credentials. If you weren't convinced of that after
reading Toby's 11/15 and 11/16 posts, you need to go back and read them
again.

And John, a double or triple plated 12.9 bolt is still a 12.9 bolt.
Probably even less due to hydrogen embrittlement after plating.

For the record the bolts in my 300HP car are frozen in place. Luckily they
are not bent, but I know they (and I) have been on borrowed time for a long
while. Whether or not this venture goes forward, one of Toby's prototype
sets will be installed this winter.

-- 
Darryl Tinnerstet
Specialty Automotive
McCleary, WA