CMS

The CMS 991 GT3/GT3RS Roll Bar is hands-down the best 991 roll bar in the business. Fully TIG welded from 4130 CrMo steel, it is the strongest, most beautifully crafted, most thoroughly engineered bolt-in roll-over protection available for the GT3-series. Get it powder-coated in one of our matched Porsche colors, or any of over 6,500 custom colors. No extra charge!

From now through Black Friday (Nov. 24), buy a CMS Performance GT3 Roll Bar and we'll include our most popular GT3 harness: the SCHROTH Profi II-6H six-point racing harness, FREE! Regularly $395, the Profi II-6H is available in black, red, silver, or blue, the perfect complement to the CMS Roll Bar. The SCHROTH Profi II-6H is designed to be comfortable with any HANS device, offering six-point protection for the ultimate in safety while the cam lock release makes entry and exit a breeze.

Just put a CMS 991 GT3/RS Roll Bar and SCHROTH Profi II-6H harness into your shopping cart and enter coupon code "RENNLISTCMS" at checkout!

Only Competition Motorsport can make an offer like this! We are the only motorsports business that designs and builds our own roll bars while also offering a full range of safety equipment like the SCHROTH Profi II-6H, along with everything else you need to get safely and successfully on track!

Mech33

How can you say that with such certainty when other vendors offer roll bars of similar design but with complex curved top bars that follow the headliner shape, providing a better cosmetic look and functional view out the back?

0to60

^^^^^^^^^^
Agree
And their exhaust tail pipes look fabulous, LOL
GMG been doing both for many years and are high quality

neurotic

how much does you guys charge for Powder Coat Color and do you have any pics of blue color?

thanks

pimpinon

Not sure about their roll cage, but I like their center section. After trying GMG, Sharkwerks, CMS, all great choices, I decided on the CMS.

0to60

Not digging the figure 8 tip design. Round or oval, guess I’m a traditionalist.

CMS

We don't charge extra for powder coating, regardless of the color. We have several different blue colors matched to different Porsche blue paint codes. Sapphire Blue is the most popular, it is a fantastic metallic color in powder! The photo below is close-up of a CMS GT4 roll bar shipping today in Sapphire Blue Metallic powder. Thanks for your question!

CMS

Thank you! We don't knock other people's products; everyone is trying to give customers a good product and good value-for-money. We intend for all of our products serve a customer for whom form follows function. Case in point is our exhaust center, which was designed with pulse scavenging as the main goal to achieve a unique sound and increased high-rpm gas flow. The "figure-eight" outlet form follows that function and we're glad so many people have embraced it! Clearly, though, it isn't for everyone.

CMS

Design isn't everything in roll bars, but it is important. We have found through racing -- and sometimes crashing -- cars that the main hoop is more structurally sound in a roll-over if it has as few bends as possible, its main purpose being absorption and transmission of crash energy to the car's frame/substructure. Rounded and kinked bars deform less predictably and transmit energy less effectively. Hence our design uses more straight sections while still fitting beautifully within the 991 cockpit and not obstructing the rear view in any way. Granted, multi-curved bars follows the headliner of the GT3 better, but that's not our main focus in adding a roll bar to a track-bound car. Call it a difference in philosophy.

Additionally, materials are important as well. We use only 1.75" .120-wall CrMo tubing throughout our bar. Most of our competitors use a combination of 1.75" and 1.50", 0.095-wall tubing; smaller and thinner. We locate the harness bars for your shoulder straps close to the driver's seat, where racing seat manufacturers recommend they be (within 12"). Others do not, they locate them far back on the rear kickers (again a by-product of that multi-curved main hoop). That's simply less safe.

So there really aren't as many similar bars as you might think, and now you have a bit more info to make the choice that's right for you. Thanks for the question, let us know if you have more!

Mech33

Thanks for the reply. Though as an engineer, I’m not buying your implication that the slight curve to the top hoop bar is compromising the effectivenesss or the roll bar structure. But if you have any actual data or models to show this, I’d love to see it.

Any thoughts on why it appears Porsche designs their 991 Cup Cars with a less safe extended shoulder harness attachment like that?



Great to have choices! Though I think some vendors go a bit too far on claiming biased marketing opinions as fact. Ideally great products can just stand on their own with the facts without embellishments.

CMS

As an engineer, I'm sure you understand that it's impossible for us to know why someone else did or didn't do something in their design and fabrication; you'd have to ask them. Let us know what you find out from your research. What we do know from the information published by race seat and harness manufacturers is there is a harness length and harness angle which provide the best protection to drivers and our CMS roll bar designs for the GT3 and GT4 meet those specifications.

There are two reasons for this (given by seat and harness manufacturers). First, because belt webbing in a harness will stretch up to 20% of its length in a collision. The longer the webbing, the more travel that allows the driver's body to make, potentially letting it move outside the seat or (in the case of a race car) the safety cage. Second, because in a side impact, the closer the shoulder belt attachment points are to the driver, the more likely it is that he will stay securely belted in his seat as the seat, cage, etc. move sideways.

Porsche's design may have other elements taken into account; you'd have to ask them what those are.

Hams955

I already have belts. I'd love to order your bar without belts and reduce the cost of the bar. Possible? GT Silver please....

- Chris.

CMS

For those of you who really geek out on this stuff (like we do!):

From Schroth Harness Installation Instructions regarding the shoulder belts: "For the best restraint of the occupant’s upper torso, ideal anchor points should not be further back than 200 mm [8”] from back of user’s seat...Extremely long shoulder belts allow for extra elongation and head movement and should be avoided. Long shoulder belts also provide more slack during the rebound phase so the belts may slide off the occupant’s shoulders or HANS. SCHROTH HANS-specific restraints with lower elongation rates for such strap lengths are designed."

From ISP Racing Seats: "Although brevity is necessary with all the belts, you especially want to keep the shoulder straps as short as possible because they are the longest pieces of the system. Any safety harness will allow a certain percentage of stretch, so the longer the belt, the more overall stretch it will allow. To minimize shoulder-belt length, the belts should mount to a rollcage bar almost directly behind the driver’s seat and approximately level with his or her shoulder blades."

Other seat and harness manufacturers make similar suggestions. Does it mean only our roll bar is safe? Absolutely not. It does, however, mean that safety is our first priority and, again, form follows function.

CMS

PM sent, Chris.

Hams955

Thanks. I haven't seen any PM come through yet.

Kind regards,

Chris.