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on my 09 NA coupe i have the thinner backbone , the pro-beam; but not the brace. is the brace worthwhile for normal driving OR is it a detriment to the other components not to have it?
Bill
 

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I have the complete set up among other things and love to drive the twisty country roads near my house that said my car handles like a go cart .It was a big improvement over my stock set up but ........ If you just want a nice comfortable ride stick with the stock set up my car ride is FIRM and that's just the way I like it .:grin:
 

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I had my car for a few months before putting on the probeam and backbone on (at the same time). I found there was a VERY noticeable increase in stability in hard cornering and, personally, would fully recommend them.

On the other hand, I later got the cross-bay (front) brace and didn't notice much, if any, difference in handling with that. Looks cool though :)
 

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Living in SE Florida, there isn't much chance to drive inclines, twisting roads etc. Would a backbone only make much difference to the ride and if it provides an advantage, which thickness would be best? I prefer a softer ride but if it helps with chassis stability and not sacrifice ride quality then I would be interested in installing one.
 

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Before probeam and backbone during hard cornering there was an obvious problem on a large bump or sudden transition where the rear of the car lunged around in an uncontrolled fashion. After installation in same conditions I would say my rear shocks' minimal compression damping is the limiting factor, but car is much more stable.

But, the surprise was the increased stability on a medium sized bump in normal street cornering where I had not actually noted a deficiency before installation. So there's my 2 cents, probeam and backbone install increased stability for normal street driving. Apparently, even grandma needs a probeam.

(I have no experience with front brace)
 

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Living in SE Florida, there isn't much chance to drive inclines, twisting roads etc. Would a backbone only make much difference to the ride and if it provides an advantage, which thickness would be best? I prefer a softer ride but if it helps with chassis stability and not sacrifice ride quality then I would be interested in installing one.
General consensus on forum is that "probeam only" is help for stability while maintaining soft ride. Backbone is less necessary and some claim soft ride suffers after install.
 

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I saw zero deterioration in ride with the Backbone and wonder how it would even have that effect as it doesn't have any impact on suspension other than to make the platform more torsionally stiff.

I agree that the Probeam works very well. I still get annoyed about a manufacturer that says, in effect "Here - enjoy our great handling sports car, but dont drive it too hard, because we saved a few bucks by making the rear suspension mounts more cheaply and if you want to drive the car hard, you are going to have to pony up more money to 'fix' what we left undone."

The DDM Probeam is much less expensive and performs exactly the same function as the GM part. But I've learned not to expect that much from GM - if guys like DDM had made the cars, the coupe wouldn't have a removable roof with no place to put it and a jury-rigged crappy looking soft top that had to be assembled like a Meccano set before you could be out of the rain.

I found the front brace to have the least effect, but nonetheless a detectable effect on the chassis. I'd say that the order should be the Backbone first, then for more serious drivers who would notice the difference, the Probeam, and for those that want the best they can achieve, add the front brace.

The majority of drivers are probably just happy tourers who would never notice any chassis shortcomings. I was used to setting up my own race cars and the first couple of days I owned my coupe, and took it out to see what the handling was all about, I found a very definite and odd point in mid-corner where the car seemed to get unsettled and then settled down again as it exited the corner. The Probeam cured that completely.
 

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As others stated the answer is yes - buy them. I planned on getting the bundle from DDM but while at NASSAM this last year PAW had a "scratched" backbone for a great deal. I got it first, then did the pro-beam, and then lastly the venom bar. As a noteworthy mention - my father was smarter than me and measured his front frame width prior to installing his venom bar. After installation he saw that the frame pulled together a little bit (I forget the exact measurements). I'm not saying that the venom bar made a drastic difference to my handling, but it seems to tie the right and left frames together solidly.
 

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Installed the pkg on my ‘09 Coupe, there is a drastic improvement in handling over stock. Highly recommend it if you want a sports car.
A transportation vehicle you drive daily you may not enjoy the firmness.
 

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I installed the 3 piece Brace Bundle on my GXP at the same time so no idea as to which item is the most effective. I waited about a year after buying the car before installing the bundle so was familiar with the stock cars handling traits. After the install, all I said was WOW. I could feel a huge improvement in the way the car handled a quick left and right turn such as a slalom at an autocross or a short S turn. No more mushy/unsettled feeling. Other than the Brace Bundle, the rest of my suspension is stock. As others have mentioned, the GXP now handles like a go cart with the braces.

I installed the 1/2" Backbone and it really stiffens the chassis. A good visual experiment is to jack up the front corner (at the proper jacking point with a puck) and measure how much the frame has to be lifted before the back tire comes off the garage floor - before and after installing the Backbone. The back tire comes off the floor a lot sooner with the Backbone. A stiffer chassis does not absorb as much of the uneven road surface since body flex is minimized and allows the suspension to do more of the work.

My 1/2" Backbone is probably overkill, a little too stiff. A 3/8" Backbone would have been adequate. But the 1/2" Backbone looks really cool with the cut outs, but you gotta crawl under the car to see it.

And I don't think that the stock GXP chassis and suspension is that bad. Many car magazines testing the Solstice gave it praise for lack of chassis flex and cowl shake. Drive any affordable first generation convertible and they all experience a lot of flex and cowl shake. It's the nature of convertibles. Without the roof structure, it's really tough to build a torsionally stiff convertible. Old MG's, Triumphs, Healey etc. were very flexible. To race them back then, first thing to install was a rollbar or cage with tubing tying the back of the car to the front to reduce the flex. And rollbars were not required at a lot of tracks back in the 60's, 70's.

I'm sure that if the Kappas had remained in production, the second generation would have addressed the issues.

The first generation Miata was not perfect, but got improved with every generation.
 

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Convertibles are normally the weaker link in any car model. Body twist, flex what ever you want to call it. The backbone brace makes the car stronger, less twist, which means less stress on the body when driving it like you stole it. I had the exact opposite feeling with the cross bay brace TS. I have the venom on the Green car and the Cross bay brace on the Yellow car. I feel much safer in the Yellow car at speed and on high speed twisty sections. It made a world of difference to me.

I have no idea why this guy really has any serious input on this. He doesn't race, has no history for him to be believed. He does car mods. There are people on this site that have far more knowledge about what the equipment does or doesn't do. NOT ME!!!!. But tuning into a website about a guys personal vehicle and buying everything hook line and sinker seems strange to me.

If I wanted true knowledge about this stuff, I would be asking Bill or Robotech, I think I would get a better answer, with a heck of lot more background information.

Not to mention they don't get paid for hits for their information.
 

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The braces make an amazing difference. The ride degrades severely, but the car is so uncomfortable for me to begin with I don't really notice. Highly recommend.
 

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I have the ddm brace sets on both my Kappas and recommend the brace kit to every Kappa owner I meet.
 

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I for one got the brace bundle & had it installed by DDM Works on my coupe. I had 2 2007 gxps & kept them stock. In all honesty the coupe seems a bit stiffer compared to my 2007s but i probably would leave my coupe stock if i did it again as i hardly push it any more in the corners. I have never raced on the track nor wrenched since the 70s so my knowledge is very limited to most on the site but i enjoy reading every ones threads as its always a learning curve.
 

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As others stated the answer is yes - buy them. I planned on getting the bundle from DDM but while at NASSAM this last year PAW had a "scratched" backbone for a great deal. I got it first, then did the pro-beam, and then lastly the venom bar. As a noteworthy mention - my father was smarter than me and measured his front frame width prior to installing his venom bar. After installation he saw that the frame pulled together a little bit (I forget the exact measurements). I'm not saying that the venom bar made a drastic difference to my handling, but it seems to tie the right and left frames together solidly.
My LS does that for me. >:)
 

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i replaced the dried out factory tires at the same time i installed the bundle so i really can't say which made the most difference. the car does ride a bit rougher but handles a lot better than it did before. i have the thick backbone. i had ordered the 3/8 one but they said they were out and offered me the thicker one at the same price. deal.
 
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