The DDMWorks Rear Pro-Beam is engineered to bring your light-duty stock cross member up to the par and exceed the bracing found on the 2006 & 2007 SCCA winning Solstices. It has been tested on vehicles lowered as much as 2" with low profile tires. It has survived over thousands of miles of abuse on roads that most of would never take their rides. Exhaust fitment has been verified with all Stock, RPI exhaust, Magnaflow*, SOLO exhaust, Borla, GM Performance and DDMWorks exhaust systems. This is the only brace to tie and link together the diff. cross member to the suspension mounting components and exceed the strength of the brace designed by GM. It is made from high quality STEEL and is seam welded and then powdercoated black for corrosion protection. Installation is accomplished with simple hand tools and an electric drill.

We often get the question of which brace should be done first to the car. Our Backbone brace and the Probeam really perform 2 different functions. The backbone is designed to stiffen the car torsionally and make a stronger platform for the suspension to work off of. On the other hand the Probeam works on the back of the cars suspension, mainly on the connecting beam that holds the rear differential. This beam flexes during cornering loads and when it does it also changes alignment on the back of the car, making the car feel unsettled in the back. The probeam stiffens this beam and therefore makes the back more solid and prevents these unwanted changes under cornering loads, making the car feel more predictable.

There has been debate back and forth on the forums and with our customers about which brace should be done first, most people end up doing both of them. The synopsis is that the probeam makes the back end feel more predictable and solid and the backbone makes the car feel more put together overall.

This improvement to the chassis does not make the ride any harsher than stock, just makes the car a more solid platform for the suspension to work off of, giving the car a ride like a more expensive vehicle.

* The 2.5" Magnaflow exhaust clears without any issues. We have installed many of them on the 3" Magnaflow systems without issues or with some slight modifications. However we have had some customers report that they could not install the Probeam with their 3" Magnaflow system though. If the Probeam is not able to fit with your particular installation for whatever reason we are always happy to refund your purchase.

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Life and Death of a Brace
With the Kappa community starting to have options in the power development of our unique platform, DDMWorks has been in development of new suspension and other components. Drawing for our extensive work with other roadster platforms, we have developed a rear structural cross member brace for your Kappa.
Beginning in the early fall of 2007, we began testing prototypes for a stiffening brace on our test Solstice. The objective was to improve on some shortcoming built into our beloved car due to the nature of production vehicles. We began with some very simple and straight forward concepts. However, our test mule proved to be quite a fighter. Feeling all good about a brace design, we merrily bolted up several prototypes and went blasting down the back roads. At least 3 different design concepts met their untimely demise this way. The problem? Our primary test vehicle is lowered and has an aftermarket exhaust. Most of the concepts that we modeled would work perfectly on a stock Kappa, but being lowered and having an aftermarket exhaust killed several designs we had spent days modeling in the computer. Below the photos show several design that, obviously, did not make the final cut.
Test Brace Version 1
Test Brace Version 2

We continued our quest with what we called the "X-brace". Very functional and VERY cool looking from the rear. But the lowered vehicle and Center exit exhaust setups still proved to be a problem.

Test Brace Version 3

Then we engaged a few GM Performance Racing engineers about the problems and what they had discovered were the weakness of the Kappa. From our track brothers in SSB & T2 SCCA racing, we discovered that it's not so much the two lower rear control arm mounts thats the problem. The engineers at GM found the cross member that holds the back of the differential in place is flexing. Although this looks to be very beefy, it is actually very thin metal filled with foam. Due to this flex, all ZOK's use a HD version of this piece. We we're able to inspect the changes they made at the factory, and tailored out new brace like-wise. To do like GM, you would have to weld additional steel in place, not for the average shade tree mechanic.

Pro-Beam Final Prototype Installed

The DDMWorks Rear Pro-Beam is engineered to bring your light-duty stock cross member up to the par with the 2006 & 2007 SCCA winning Kappas. It has been tested on vehicles lowered as much as 2" with low profile tires. It survived over 10,000 miles of abuse on roads that most of you would never take you rides. Exhaust fitment has been verified with Stock, Magnaflow, SOLO Center, GM Performance and DDMWorks exhaust systems. This is the first brace to tie and link together the diff. cross member to the suspension mounting components. It is made from high quality STEEL and is seam welded. The brace is E-coated black for corrosion protection. Installation is accomplished with simple hand tools and an electric drill.

click image to enlarge

Probeam Scale Test	Probeam kit

tested on vehicles lowered as much as 2" with low profile tires

Exhaust fitment has been verified with Stock, Magnaflow, SOLO Center, GM Performance and DDMWorks exhaust systems

made from high quality STEEL and is seam welded

E-coated black for corrosion protection

Installation is accomplished with simple hand tools and an electric drill