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Karbonius Composites BMW Chassis Reinforcement Kits & Parts

Made in the USAAs much of an "Ultimate Driving Machine" it is, many BMW models unfortunately suffer from weak points in the chassis. Over the years we have uncovered many weak or failure-prone areas in the chassis and have developed our own reinforcing solutions for them. And we continue to be the leading experts on BMW chassis reinforcing. Failures can come from a number, or combination, of causes: improper maintenance, age and mileage, poor design, environmental factors, poor repair work, and over-stressing modifications. The longer you let your car go without repairing or reinforcing these areas, the closer it gets to crumbling apart. Our chassis reinforcement kits are designed to first identify potential weak points and then strengthen and reinforce the existing design.

Most of our kits are not labor intensive although welding is usually required. If you suspect your chassis may have structural problems we recommend taking it to a well-known bodyshop or restoration shop. (find out who your local BMW dealer uses - we sell many of our kits to dealer-authorized repair shops). Making the preventative fix simple and effective is better than a long and complicated repair after the failure. Our kits are not usually used for fixing existing damage (only your body shop can determine the correct course of action). But our kits have been proven under extreme conditions on racetracks around the world to prevent many of the costly - and dangerous - chassis problems.
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Karbonius E46 M3 / 3-Series Carbon FIber Strut Brace
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Karbonius Composites - Corporate Logo
T#:28104800
Part#: E46SB01CF
Ships on Jul 22, 2026
Starting at $ 1,195.00 USD
Free Shipping on orders $49 and up
Starting at $ 1,195.00 USD
Free Shipping on orders $49 and up
A strut tower bar is one of the most common and effective upgrades in a vehicle. With the installation of a strut brace, the body gets added structural strength, preventing tower flex and alignment changes during sporty driving or while at the race track. Improve your E46-Chassis BMW with the Karbonius Carbon Strut Brace! Karbonius Composites was inspired by the popular, but no longer available BMW Performance strut bar to create a version of their own. They have designed an extremely strong and lightweight brace that not only adds strength and stability, but also a spectacular eye-catching look. The carbon strut bar is manufactured in prepreg carbon fiber and cured in aluminum mold in an autoclave; while the strut tower caps are 5-axis CNC machined, and includes titanium strut tower nuts. Installation Instructions Product Details: Fits all E46 and M3 Offered in standard high gloss, 2x2 carbon weave Natural anodized aluminum strut tower caps 6 titanium nuts included Very light, only 1100g weight Perfect fitment and easy installation 100% carbon fiber prepreg Cured in aluminum mold and autoclave Controlled break zone Exclusive and numbered piece 2-year warranty NOTE: All pieces are numbered to guarantee authenticity and origin.
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Karbonius E36 M3 / 3-Series Carbon Strut Brace
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Karbonius Composites - Corporate Logo
T#:28104803
Part#: E36SB01
Back Ordered
Starting at $ 839.00 USD
Free Shipping on orders $49 and up
Starting at $ 839.00 USD
Free Shipping on orders $49 and up
Strut tower bar is one of the most common and effective upgrades in a vehicle. With installation of strut bar bodywork gets structural strength, preventing tower flex and alignment changes during sporty driving. Improve your BMW with Karbonius strut bar and prepare for people staring! In Karbonius Composites, we have inspired in E46 BMW performance strut bar to create our own strut bar. We have designed a piece extremely strong but light at the same time, what adds not only strength and stability, but also a spectacular eye-catching look. A strut bar manufactured in prepreg carbon fiber and cured in aluminum mold in autoclave; CNC machined manufactured in 5-axis machine. Standard finish includes varnish high gloss and natural aluminum anodized. Product Details: Fits all E36 and M3 2x2 weave Very light, only 1150 grs weight Perfect fitment and easy installation 100% carbon fiber prepreg Cured in aluminum mold and autoclave Controlled break zone Exclusive and numbered piece 2-year warranty NOTE: All pieces are numbered to guarantee authenticity and origin.
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G8X M2 / M3 / M4 CSL Carbon Front Strut Brace
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Karbonius Composites - Corporate Logo
T#:26471475
Part#: G8XSB02-CF-AB
Ships in 3 Business Days
$ 3,115.00 USD
Free Shipping
$ 3,115.00 USD
Free Shipping
M4 CSL brace has been designed to enhance the sportive character of M cars, at the same time as it brings the best rigidity to the chassis. Designed and manufactured in Spain under strict quality requirements according to UNE-EN ISO 9001:2015. This piece is made by hand with the best carbon fiber prepreg. This piece is manufactured by combining craft and technology. On the one hand, with the care and attention to detail that characterizes our company, and on the other, with the use of the most modern equipment in some critical points of the process, such as 3D scanning, autoclave curing, and robotic cutting. The G8X CSL strut brace has been manufactured with monobloc tubular technology, avoiding unnecessary joints that could result in weak points. Lamination has been carefully designed, and we include 3 different fabrics, all best quality, including high-modulus unidirectional carbon. 6061 aluminum machined components complete the piece providing great resistance to wear in the area of joint to the chassis. Not just to save weight, but to achieve the strength and rigidity necessary for a functional part with similar characteristics to the OEM part. The result? A piece with an OEM finish and fitment, but with an awesome appearance and only 1.8 kilos, which is a significant weight reduction compared to the original bar which is 3.5 kilos.
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