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X-Brace Chassis Reinforcement Upgrade (034Motorsport) for B8 A4-S4-RS4 A5-S5-RS5 Q5-SQ5

SKU: 034-603-0008
034Motorsport's B8 Audi A4-S4-RS4 A5-S5-RS5 Q5-SQ5 X-Brace Chassis Reinforcement Upgrade is designed to replace the factory front subframe brace to increase torsional rigidity, resulting in improved steering feel and handling performance. Machined at 034Motorsport from T6-6061 billet aluminum, the 034Motorsport X-Brace is engineered to outperform the stock welded, stamped steel part and ensure that suspension geometry is not compromised by chassis flex under hard cornering.

The beautifully-crafted X-Brace is a direct, bolt-in upgrade for both B8 and B8.5 chassis vehicles, and offers more direct and consistent steering feel, and better handling, without sacrificing comfort.

The factory Audi front subframe brace is manufactured from multiple pieces of stamped steel, and allows for performance-hindering chassis flex under load. This torsional flex can result in improper suspension geometry and alignment when cornering, and leads to vague steering feel and lack of steering precision.

This chassis brace upgrade was thoroughly tested by 034Motorsport and independent Audi enthusiasts before release. Installation is very simple, can be performed in minutes, and is completely reversible.

- T6-6061 Billet Aluminum Construction
- CNC-Machined In-House
- Clear Anodized Finish for Durability
- Engineered to Replace Factory Front Subframe Brace
- Drastically Reduces Chassis Flex When Cornering
- Enhances Handling Dynamics and Performance
- Improves Steering Feel, Consistency, and Precision
- Will Not Cause Additional NVH Transfer Inside Cabin
- Modular Design Fits Both B8 (Pre-Facelift) & B8.5 (Facelift) Models
- Easy, Straightforward Installation!

What's Included:
- 034Motorsport Billet Aluminum X-Brace Chassis Reinforcement (Fits B8-B8.5 Audi A4-S4-RS4, A5-S5-RS5, Q5-SQ5)
- Modular X-Brace Inserts (Set of 2)
- M10 X-Brace Assembly Screws (Set of 4)
- M5 Undercarriage Tray Mounting Screws (Set of 4)
- 15mm Undercarriage Tray Mounting Washers (Set of 4)

Installation Instructions:
- Web - PDF
- Product Information Sheet

- 2009 - Present Audi A4 (B8/B8.5), All LHD Models
- 2010 - Present Audi S4 (B8/B8.5), All LHD Models
- 2013 - Present Audi RS4 (B8/B8.5), All LHD Models
- 2008 - Present Audi A5 (B8/B8.5), All LHD Models Except Cabriolet
- 2008 - Present Audi S5 (B8/B8.5), All LHD Models Except Cabriolet
- 2013 - Present Audi RS5 (B8/B8.5), All LHD Models Except Cabriolet
- 2008 - Present Audi Q5/SQ5 (B8/B8.5), All LHD Models

Replaces OEM Part Numbers:
- 8T1 399 345 J or 8T1399345J
- 8K1 399 345 E or 8K1399345E

Please Note:
- Fits LHD (Left-Hand-Drive) Vehicles Only. Does Not Fit RHD (Right-Hand-Drive) Vehicles.
- Does Not Fit Cabriolet.
- We recommend using new factory stretch bolts to install the X-Brace. Complete factory bolt kits are sold separately in this same section. There are two different bolt kits: a B8 (Pre-Facelift) X-Brace Bolt Kit and a B8.5 (Facelift) X-Brace Bolt Kit.

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This product fits the following vehicles:
Make Model Chassis Engine
Audi Q5 B8 (2009-Present) all
Audi RS5 B8-B8.5 (2011-2015) 4.2l V8 32v FSI
Audi S5 B8-B8.5 (2008-2017) all
Audi A4 B8-B8.5 (2009-2016) all
Audi S4 B8-B8.5 (2010-2016) 3.0t V6 24v SC
Audi A5 B8-B8.5 (2008-2016) all
Audi S5 B8-B8.5 (2008-2017) all
Audi SQ5 B8 (2014-Present) 3.0t V6 24v SC
Customer Reviews (1)
Great PRODUCT!!! Steering and handling feels sensational. Great modification to stiffen up ride. Such a beautiful piece of craftsmanship!!! Review by Martez (Posted on 4/19/2016)
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You're reviewing: X-Brace Chassis Reinforcement Upgrade (034Motorsport) for B8 A4-S4-RS4 A5-S5-RS5 Q5-SQ5
Off-road Use

By Purchasing any Off-Road use ONLY products from JH Motorsports, Inc. I acknowledge and understand the following disclosure. (This notice is located at the bottom of the page description of affected products on our website.)

Vehicle Code § 27156:
(b) No person shall operate or leave standing upon a highway a motor vehicle that is required to be equipped with a motor vehicle pollution control device under Part 5 (commencing with Section 43000) of Division 26 of the Health and Safety Code or any other certified motor vehicle pollution control device required by any other state law or any rule or regulation adopted pursuant to that law, or required to be equipped with a motor vehicle pollution control device pursuant to the National Emission Standards Act (42 U.S.C. Secs. 7521 to 7550, inclusive) and the standards and regulations adopted pursuant to that federal act, unless the motor vehicle is equipped with the required motor vehicle pollution control device that is correctly installed and in operating condition. No person shall disconnect, modify, or alter any such required device.
(c) No person shall install, sell, offer for sale, or advertise any device, apparatus, or mechanism intended for use with, or as a part of, a required motor vehicle pollution control device or system that alters or modifies the original design or performance of the motor vehicle pollution control device or system.

Health and Safety Code § 43000:
43001. The provisions of this part shall not apply to:
(a) Racing vehicles.

As the aforementioned code sections outline, it is against the law to operate or use a vehicle on public streets or highways with modified, altered, or disconnected motor vehicle pollution control devices. This may include but is not limited to, Evaporative Fuel Controls, Catalysts, DPF, PTOX, PCV Systems, Exhaust Gas Recirculation Systems, Oxygen Sensors, Thermostatic Air Cleaners, Air Intake Systems, Fuel Injectors, Regulators, Adjustable Cam Gears, ECU Programming, Mapping, or other Computer Modifications. Air Pumps, Air Injection, Timing, and any other Emission System Modification(s).

Purchaser acknowledges and certifies to JH Motorsports Inc., that Purchasers vehicle will only be used for racing applications or off road vehicle use only. Purchaser requests these modifications for the purpose of enhancing the vehicle for competitive Racing Applications and will not use this vehicle on public streets or highways. Purchaser agrees to indemnify JH Motorsports Inc., all employees, officers, owners, and subsidiaries for any civil or criminal liability arising out of use of Purchasers vehicle on public streets or highways as Purchaser has been duly notified of the laws and regulations regarding disconnecting, alteration, or modification of a vehicle’s pollution control devices. Purchaser understands and has been advised the driving of a vehicle on public streets or highways could result in criminal or civil penalties.

Prop 65

Warning: This product may contain a chemical known to the State of California to cause cancer, birth defects, or other reproductive harm.

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Q and A

Product Questions

Besides the decrease in chassis flex is there a weight saving over the stock x-brace? If so how much?
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