Strut-tower Brace? We don't need no stinkin' strut-tower brace!

[TBone]

So Car and Driver's Tech Department did an article about a K&C Machine which cost about $3 million and really tests a chassis/suspension/etc.

One of the comments from the gentlemen that runs this machine will be an eye opener for some and Pfadt did a test that came to the same conclusion with just a string (I can not seem to find the video though).



Discuss...

T.

GO HAWKS!!!!!

[family man]

Yea, but they look so cool! And yes, I have one.

[Moreno1]

That is one awesome piece of equipment.

nice article! And another indicator that Pfadt is on top of their game.

[malave7567]

I have one for looks alone. Pedders also says our cars get zero benefit from a strut brace. The only Camaro requires it is the Vert (and that's why it comes with one).

[Norm Peterson]

Originally Posted by TBone

So Car and Driver's Tech Department did an article about a K&C Machine which cost about $3 million and really tests a chassis/suspension/etc.

One of the comments from the gentlemen that runs this machine will be an eye opener for some and Pfadt did a test that came to the same conclusion with just a string (I can not seem to find the video though).

Discuss...

T.

I've posted this content (more or less) at various times and on various forums. Mention of this C/D article came up on a rather more technically oriented forum, so maybe I'll see how close I am.


The most likely performance improvement for any two-point bar would be under severe braking where the two tower tops will be moving in opposite directions (rather than in the same direction by slightly different amounts as is the case while cornering). It would take at least a three-point strut tower tie bar configuration involving the firewall/cowl structure to add enough general torsional stiffness to even begin to matter as far as chassis torsion is concerned, and I'm sure that an X-braced four point arrangement attaching out near the A-pillars would be better still.


Buick installed two point strut tower braces as OE on at least some of their sedans only a few years back, but I doubt that its effects on either cornering performance or handling balance were considered as being much more than incidental to reductions in NVH and cowl shake . . . which also addresses quite nicely the anecdotal claims of "feels more solid" by those who have fitted STBs to cars that do not feature them as standard structural fitments.

Even the much larger cross-section two point lower lateral tie that I added to a different chassis was more noticeable for the changes it made in NVH than in any easily recognized improvements in autocross performance.


Norm

[jeremywes]

Mine gives me 3 extra HP and 4 lbft of torque. ;-)

[jeremywes]

I agree that the STB doesn't make your car handle better or improve a paticular deficiency however if you are testing multiple suspension setups and trying to dial in your car for a given track it will allow you to get more percise settings without chasing grimlins because your strut tower deflection is dynamically changing your intended settings. I can prove it with some chaulk and a tire heat probe.

[Dizzy82]

I like my GM brace, even if it doesn't provide any "measurable" difference. By looks alone I love it.

[alcal1084]

not sure how much track performance you get, but i do know first hand it makes a difference on how the car feels!!! i took a drive up the rachel NV out by area 51 over a year ago and let me tell you the road is SHIT. tried to go fast and the wheel was all over the place the car felt like it was falling apart... flash forward to a few months back went out for the same cruise and i kept thinking to myself wow they fixed the road the wheel wasn't moving the car felt more solid!! the only thing i changed on my car was put a GM strut brace trust me it makes a difference!!!

[Norm Peterson]

Originally Posted by Dizzy82

I like my GM brace, even if it doesn't provide any "measurable" difference. By looks alone I love it.

Which is an entirely valid reason.


I was hoping that this particular individual would reply over in that other forum.

Originally Posted by OE automotive engineer

While it is 'obvious' that a stiffer car will handle better, it is actually rather hard to measure. On the other hand if a particular mounting point is /severely/ deficient then rectifying that by bracing can make a measurable effect. Having said that, I am quite happy to go along with the subjectivist viewpoint that we can't actually measure every last detail of what makes the driver happy (yet) so there is still some wiggle rooom, and damper tuning in particular (and hence shock absorber mounting points) is still a bit of a black art. So while it may be hard to model an improvement in lap times from a stiffer shell, or a strut brace, I can quite believe that one way or another it helps. The benefits in shake,secondary ride, or structural feel, or whatever you like to call it are directly measurable.

My guess is that we'll need another factor of 2-4 in transducer density and modelling accuracy before we'll catch that sort of nuance in steering/handling.

If we go the other way and look at ladder frame pickup trucks, then the stiffness of the ladder frame is an integral part of the vehicle's handling, trying to get a good grip on modelling the truck for handling assuming a a rigid chassis is fraught with difficulty.

I think that roughly translates as "there is a performance benefit in adding these braces, but it's too small to reliably predict unless the chassis in that region is only slightly stiffer than a wet noodle. Benefits on the NVH side of the coin are easily measured/predicted".


Norm

[PAUL SS]

Originally Posted by jeremywes

Mine gives me 3 extra HP and 4 lbft of torque. ;-)

And five more pounds of weight.

[Doubleblank]

And, once again I'll bring up the various teams racing Camaros in World Challenge and Grand Am where slight improvements in car speed into and thru corners is the difference between the podium and everyone else. Some use them and some don't. When we raced Camaros, we didn't. But they do look good for sure.

[jeremywes]

Originally Posted by PAUL SS

And five more pounds of weight.

This is tru... damn, I try to forget about that

[TBone]

Bump.

T.

GO HAWKS!!!!!!!!