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MNBoxster · 01-13-2006, 02:57 PM

@ESLAI,

Hi, while I don't necessarily disagree with you out-of-hand on all points, I'm not really certain what your Ad Hoc test really proved. It's probably safe to assume that one would expect the Car's chassis to accept it's own weight, whereas in Real-World application the added inertia from maneuvering can increase the weight greatly, possibly in Factors of the Vehicle's actual weight. This is where a Car's Rigidity is challenged.

Preventing the Strut Towers to oppose, or move independently of, each other does have an effect toward stiffening the Chassis because the Strut Towers will move Mostly laterally and the Bar will prevent this. Admittedly there is also some Fore and Aft movement, but there are additional braces on the Car's underside to help minimize this. Assuming some still remains, at least you've eliminated some part of the equation and that is worthwhile.

Also, tying the two Towers together effectively completes a circle with the Floor (chassis for all intents and purposes on a Uni-Body Car) which can then absorb (oppose actually) the forces imposed on it by the maneuvering suspension. And the suspension on that axel acts much more in unison while still preserving independent action.

I agree there are some Cars out there which do not benefit from such bracing, but for the Boxster I consider it most complimentary. I also agree that a Full RollCage adds even further Rigidity.

My own Ad Hoc test with the Braces showed positive results. I live on a twisty road and there is a very tight HairPin turn .5 mi. from my house. I have lived here many years and know this turn like the proverbial Back of My Hand. Over that time, this HairPin has served as sort of an Acid Test for all my Cars. Prior to adding the Front Brace alone, I could take this turn at 38MPH before the Rear got skittish, Tires squealing, etc. After the Front Brace, I raised the Bar to 43MPH. After the Rear was added, I could go through this turn at 52MPH before teetering on the edge. And, virtually all the annoying creaks, groans, and rattles are gone - something good is going on here...

Happy Motoring!... Jim'99

01-13-2006, 02:57 PM	#14
MNBoxster Registered User Join Date: Sep 2005 Location: Minneapolis/St. Paul, Minnesota, USA Posts: 3,308	@ESLAI, Hi, while I don't necessarily disagree with you out-of-hand on all points, I'm not really certain what your Ad Hoc test really proved. It's probably safe to assume that one would expect the Car's chassis to accept it's own weight, whereas in Real-World application the added inertia from maneuvering can increase the weight greatly, possibly in Factors of the Vehicle's actual weight. This is where a Car's Rigidity is challenged. Preventing the Strut Towers to oppose, or move independently of, each other does have an effect toward stiffening the Chassis because the Strut Towers will move Mostly laterally and the Bar will prevent this. Admittedly there is also some Fore and Aft movement, but there are additional braces on the Car's underside to help minimize this. Assuming some still remains, at least you've eliminated some part of the equation and that is worthwhile. Also, tying the two Towers together effectively completes a circle with the Floor (chassis for all intents and purposes on a Uni-Body Car) which can then absorb (oppose actually) the forces imposed on it by the maneuvering suspension. And the suspension on that axel acts much more in unison while still preserving independent action. I agree there are some Cars out there which do not benefit from such bracing, but for the Boxster I consider it most complimentary. I also agree that a Full RollCage adds even further Rigidity. My own Ad Hoc test with the Braces showed positive results. I live on a twisty road and there is a very tight HairPin turn .5 mi. from my house. I have lived here many years and know this turn like the proverbial Back of My Hand. Over that time, this HairPin has served as sort of an Acid Test for all my Cars. Prior to adding the Front Brace alone, I could take this turn at 38MPH before the Rear got skittish, Tires squealing, etc. After the Front Brace, I raised the Bar to 43MPH. After the Rear was added, I could go through this turn at 52MPH before teetering on the edge. And, virtually all the annoying creaks, groans, and rattles are gone - something good is going on here... Happy Motoring!... Jim'99