Hmmm.... I believe that he has installed my version, and is looking to place actual sensors on the bottom of his car in order to come up with some "raw data" that will equate to a conclusion.
Greg, look at your poll, I posted a proposition

 

Correct Mark. I had installed it and taken it up the local canyon once. In my (SOP) opinion I noticed a difference right out of the driveway. For any dynamics freaks out there, I'm going to try to install some Kistler Accelerometers this weekend. The accelerometers will be fed to a charge amp and the 4 (or 5) channels recorded. I have baseline data from a while back when other X-Brace developers asked if the movement could be quantified. At that time I used 4 (my mistake as I did not use a "no flexture" reference point;(. At that time it ran .025 to .070" of flexture from point to point under heavy cornering. I'm hoping to use the same plot scales and overlay them. I know the corner I did the data dump in last time. My only question is whether I can get a hold of the right equipment. Most of it is down in Brazil being used to check bending moments on the Embraer 145 Regional Jet........fingers crossed.

 

Utah S2k-

Forget all the debates. There are more important things to look into...

You may want to also test the difference in the flex of the chassis. I would assume (again, intuition, please correct me if I'm wrong) that without the brace the chassis, from front to back, would have a stable, predictable amount of flex. What does an X brace do to this, and are there stress risers that are introduced with this product that could weaken the chassis in the long run- specifically at the junction area where the brace ends?

Another question I have is- tying the bottom of the chassis may work well in practice (as so many of you have vouched for the effectiveness of the brace) but in design it sort of doesn't make too much sense at first glance. When you're tying four "floating points" down (the points that the brace is bolted to) you've set their distances to each other based on the elongation, expansion and contraction characteristics of the brace material and design. However, the brace doesn't do one thing- it doesn't tie those four points to a reference point that is common to the upper chassis. What you may (and I stress the word "may" being purely speculative) end up with is a tied down lower chassis subframe that "floats" according to the dynamic flex of the vertical members of the front chassis, and on top of that, would be subject to undetermined changes due to temperatures, the design and material of the brace, unless constantly relieved (loosened and rebolted often). How accurate the chassis has to be is also an undertermined factor- does the 2.5/100th of an inch to 7/100 of an inch of flex that you measured make that much a difference on the handling of the car, or is there even more deflection elsewhere, say maybe the suspension arms, or are there suspension components that depend on the flex to minimise impact force that may cause failure? In other words- how much compliance in the chassis can we limit without any parts failure? Without extensive CAD files and FEA, that would be pretty hard to determine without extensive R&D, and even with those tools it would be difficult.

The brace may (again, being purely speculative) be an answer to the question of flex, but may not be the best answer with all the given positives and negatives that again, may be discovered in your research. I have no bone to pick with this one- I hope you can come up with some useful knowledge for the board.

For the record I don't use a lower chassis X brace and don't know the effects of one on the S2000.

 

Interesting thoughts, GTRPower. Fwiw, I noticed a stiffening over bumps and potholes after stb brace addition. I then added a Neuspeed front lower brace that replaces the stock lower brace, but is much more rigid. I did not notice much change, but perhaps some. It may be that replacing a stock lower brace with a stiffer one rather than placing an "x brace" may also allow speculation along the lines you have presented, but perhaps the effects would be less.

 

I have a Spoon brace and a loaner Digrappa brace.

After installing the Spoon brace, It certainly felt like the car was stiffened and handling was crisper. After installing the Digrappa brace, it felt again like the car had been stiffened even more, with even crisper turn in and rough road stability.

Of course all of this was seat-of-the pants on some local twisty roads. I've been intending on doing some A/B tests at the local track, but keep getting delayed on track time due to weather and track availability.

The latest track day is next Friday (Second Creek Raceway), and I intend on trying to turn some repeatable lap times with the Digrappa, Spoon and no X brace. Unforutunately, I'm not sure my driving skill is high enough to eliminate the driver variable from the equation. We'll see! Anybody who wants to come by and help time, change braces, or even take a few hot laps is welcome.

 

[QUOTE]Originally posted by Rick Hesel
[B]I particpated in part of the session.

 

Please keep in mind that pfb did notice a difference over the Spoon, and does not own one of my braces, as he said, it is on loan, and he therfore has no obligation to state anything but the facts. I am truly interested in seeing the results of the tests as well.
As for longevity Nick, I have no idea, and you do have some interesting thoughts. In fact, a couple of years back the same discussion took place on the BMW board about STBs and their affects. They are still in use today, even though some people do not have them, the people that do have not reported any problems, but I guess only time will tell. Thanks for your valuable insight
Mark DiGrappa

 

I can understand feeling a difference brace v. no brace. I cannot accept butts feeling a difference between brace x v. brace y. As sensitive as some of your butts may be, this is just straight-up hype talk.

Utah, you know I'm still not over your my-Tochigi-bud-says-no-2002-for-sure-dream-on posts.

 

[QUOTE]Originally posted by mdigrappa
[B]...As for longevity Nick, I have no idea, and you do have some interesting thoughts.

 

While quantifiable measurements are cool and all, instrumented measurements don't always translate well to the driving experience. It would be cool to know that points A and B flex Y inches during X, and only flex Y/n inches with the brace. The problem is that such a measurement/test/result doesn't _prove_ a thing when it comes to real world improvements in handling.
What I'd like to see is a set of blind timed runs, say through a slalom or auto-x course. Multiple runs with multiple drivers, without the drivers being told if the brace is on or not. If these things are as effective as the claims make them out to be, there should be significant and reproducible improvements in the performance of the selected course. Not that I'm a cynic or anything