Strut Tower Brace Design Revisited

SuffolkD at SuffolkD at
Mon Feb 28 21:04:39 EST 2005

Strange you'd snip someone copying your "design", comedy or not.
"Stick to your CEOing, George."

While it may keep the strut inserts aligned when the bearings or other 
components are worn, there's deflection/twist in the chassis that your brace doesn't 
account for.

As Peter says, your test conditions are far smoother than ours, and unless 
you drive by Braille ON the lane markers on the I-5, you'd never see the chassis 
flex which may show the potential short comings of the EMT in your design, or 
the design itself.

I also seem to remember an engineer who also chimed in on the list a year or 
two ago telling how dangerous he thought your design was.

Personally, I feel there is a reason the factory went with a tower brace 
(specifically) as Bernie you corrected me on my generalization of "strut brace."

The twist of the chassis from pot holes, understeer/oversteer while in 
motion, elevation changes in mid turn, steep bisecting parking garage exit ramps 
(while turning) like in California, curbs and the like.
This is easily duplicated by jacking the car up at a jack point then trying 
to open the door.  Chassis flex on an inferior design is evident when you try 
to open the door.

This twisting of the frame is not addressed by your brace, but by every other 
suspension component (in line between your brace and the applied twisting 
force) until the last bit of strut movement which your brace bridges.
Maybe IMHO that's why you haven't seen a failure in compression/tension of 
the EMT. Its the bushings, strut bearing and other components that have 
sacrificed themselves ahead of your EMT.  Either that or the sidewall of the tire is 
weaker that the EMT.

IF I was to use your "intriguing" strut brace idea I'd go the George route, 
SOLID bar. but I'd also go "tower" brace ala Audi.

If there was a design flaw in the VAG tower brace (next to cost) I'm sure 
they'd quickly adopt your brace idea as a cost cutting measure.  The accountants 
would push for it.
-Scott by BOSTON

> From: Peter Schulz <>
> Sorry, but your design is engineered no more or less than Georges....
> Bottom line is that we all have our opinions - in the absence of the real 
> science of suspension design with force measurements and analysis
> "If your rational were true, my strut brace designed for compression forces 
> only, would have hammered itself to pieces by now, under your osculating 
> tensile forces.  Rather, it shows no sign of the tubing ever leaving the 
> jam nuts, the design intent."
> What does that mean in respect to the road environment where you live?  If 
> your roads are relatively smooth, you would likely see alot less strain 
> then on uneven, poorly maintained roads.

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