Anti Roll Sway Bar

Front and rear anti roll bar set 5 way adjustable. 

Fits:
Porsche 981 Boxster / Boxster S - 2012 to 2016
Porsche 981 Cayman / Cayman S - 2013 to 2016
Porsche 718 Boxster / Boxster S / Boxster T/ Boxster GTS - 2017 Onwards (2.0lt and 2.5ltr models)
Porsche 718 Cayman / Cayman S / Cayman T/ Cayman GTS - 2017 Onwards (2.0lt and 2.5ltr models)

The Best Suspension Mod Available for the Porsche 981 and 718

Through extensive research and track testing, CMS has engineered the perfect replacement sway bars for the Porsche 981 & 718 Cayman/Boxster (all model) Our engineers took hundreds of laps at racetracks from Road America to COTA, Mid Ohio to High Plains, along with thousands of miles on the street. All to confirm the CMS Performance Sway Bars transform the handling of the Porsche while maintaining the car's everyday driveability and reliability.

Tuned to work with your Porsche's OEM struts and springs (both standard and PASM), the CMS Sway Bars are the best handling improvement you can make to your 981. Based on the sway bars of the GT4, the CMS Performance Sway Bars have five holes of adjustment both front and rear, giving you an unprecedented range within which to tune your car's handling depending on the road or track you're tackling.

Larger Diameter Plus  Fine-Tuning Your Porsche's Handling

With larger diameters than the OEM GT4 bars, the CMS Performance Adjustable Sway Bars can be adjusted from slightly softer than stock to substantially stiffer. This lets you fine-tune handling balance from understeer to neutral to oversteer with simple hand tools.

Included are OEM Porsche sway bar bushings, precision-machined for the slightly larger bars, giving you worry-free fitment, OEM quality, and a noise-free installation. CMS Performance Sway Bars are engineered and manufactured in the USA with drop-forged ends for high strength and performance.

Base, S, GTS models have CMS front drop links. These are OEM Porsche front links customized to fit the CMS front sway bar. Your original rear drop links do not need to be replaced.

CMS Performance Adjustable Sway Bars Details:

• Diameters of 31.8mm (front) and 25.4mm (rear), 30% larger than the OEM 981 Cayman GT4 bars
• Adjustment of each bar goes from 1% softer than stock to 50% stiffer.
• Powder-coated Black, Red, or Silver for long life and great looks
• Designed and manufactured in the USA using all US components
• Engineered specifically for the Porsche 981 and 718 chassis

Adjustable Sway Bar Kit Includes the Following:

• Front and rear five-way-adjustable sway bars w/ forged ends
• OEM Porsche bushings custom-machined to our specifications
• OEM Porsche front drop link set, customized to our specification (required for Base, S, GTS)

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

991343705CMS

The product you are viewing cross references to these numbers

H&R Sway Bars are the perfect compliment to H&R Springs, Coil Overs, Performance Shocks and Cup Kits.



Front & Rear Anti Roll Bar:
- Front - 28mm (not adjustable) requires bushes 99134379208
- Rear - 24mm (adjustable in 2 places)

Fits:
Porsche 981 Boxster / Boxster S 05/2012>>
Porsche 981 Cayman / Cayman S 05/2012>>

Designed to reduce body roll, increase lateral stiffness and improve handling. All H&R Sway Bar kits have been shot peened and heat treated, and feature precision forged ends - many applications have multiple end link mounting points for adjustability. Also included are H&R exclusive bushings made from a Urethane / Teflon composite that eliminates squeaks, and don't require lubrication. Ever. That means no mess, no maintenance-just bolt in H&R Sway Bars and go!
H&R Sway Bars are 100% made in Germany, and are powder coated for long lasting good looks and durability on the street and track.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

33879-1

The product you are viewing cross references to these numbers

Rear anti-roll bar 98133370314 by Porsche for selected 981 Boxster, 982 Boxster and 982C Cayman applications from 2012 onwards. This genuine rear stabiliser must be selected using the applicable vehicle PR codes.

Fits

• Porsche 981 Boxster 2.7L / Boxster S and GTS 3.4L 2012–16 — PR:009,X73 or PR:008,X73 as specified by the parts diagram
• Porsche 718 Boxster (982) 2017>> — 2.0L 300 Bhp base and T, 2.5L 350 Bhp S, 2.5L 365 Bhp GTS, 4.0L 400 Bhp GTS and Boxster 25 Years, including listed manual and PDK variants — PR:219,475477
• Porsche 718 Cayman (982C) 2017>> — 2.0L 300 Bhp base and T, 2.5L 350 Bhp S, 2.5L 365 Bhp GTS and 4.0L 400 Bhp GTS, including listed manual and PDK variants — PR:006,030; PR:029; or PR:219,475477

Check fitment for your specific vehicle (model, year, engine) before ordering. Confirm the part number and PR codes against the VIN because visually similar stabilisers can have different specifications.

Diagram: Anti-roll bar 981 Boxster / Boxster S 2012-16

Diagram: Anti-roll bar 718 (982) Boxster 2017>>

Diagram: Anti-roll bar 718C (982C) Cayman 2017>>

What This Product Does

The anti-roll bar connects the left and right sides of the rear suspension. By resisting differences in suspension movement across the axle, it helps manage body roll and preserves the chassis balance specified for the vehicle.

Functions

• Resists excessive lateral body movement during cornering
• Connects suspension movement across the rear axle
• Helps maintain the intended front-to-rear handling balance
• Transfers loads through the stabiliser mountings and coupling rods

Technical Details

• Part number: 98133370314
• Catalogue description: anti-roll bar; stabiliser; stabilizer
• Position: rear axle
• Brand: genuine Porsche
• Diagram quantity: 1
• Application identifiers: PR:009,X73; PR:008,X73; PR:219,475477; PR:006,030; PR:029

Symptoms of Fault

• Greater body roll or inconsistent behaviour through corners
• Visible corrosion, bending or other physical damage
• Excess movement around the mounting locations
• Clunks or knocks when travelling over uneven surfaces
• Unsettled response during quick changes of direction

Suspension noise does not necessarily indicate a defective bar. Worn bushes, coupling rods, brackets or fasteners are more frequent causes, so the complete stabiliser assembly should be inspected before parts are replaced.

Why Replacement Matters

A bent, damaged or incorrectly specified stabiliser can change the suspension characteristics intended for the car. Installing the correct PR-code-specific Porsche part helps retain the original rear chassis configuration. Inspect the associated bushes, clamps, brackets, links and fixings while access is available.

FAQs

• How is the correct anti-roll bar identified?
  Compare part number 98133370314 and the listed PR codes with the vehicle VIN and factory equipment data.
• Is the anti-roll bar always responsible for rear suspension knocks?
  No. Check the bushes, coupling rods, brackets and mounting hardware first, as wear in these components commonly causes noise.
• Are bushes, brackets and coupling rods included?
  These are separate parts within the stabiliser assembly and should be assessed individually.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

98133370314

The product you are viewing cross references to these numbers

Ultra Racing 4 Point Rear Lower Brace.

The Ultra Racing rear lower brace is designed to increase rigidity across the rear section of the Porsche 981 chassis by connecting key mounting points around the rear suspension and subframe area.

Fits:

• Porsche Boxster 981 2.7L 2012-16
• Porsche Boxster 981 S / GTS 3.4L 2012-16
• Porsche Boxster 718 2.0L Manual (300 Bhp) 2017>>
• Porsche Boxster 718 2.0L PDK (300 Bhp) 2017>>
• Porsche Boxster S 718 2.5L Manual (350 Bhp) 05/2017>>
• Porsche Boxster S 718 2.5L PDK (350 Bhp) 05/2017>>
• Porsche Boxster T 718 2.0L Manual (300 Bhp) 01/2019>>
• Porsche Boxster T 718 2.0L PDK (300 Bhp) 01/2019>>
• Porsche Boxster GTS 718 2.5L Manual (365 Bhp) 05/2017>>
• Porsche Boxster GTS 718 2.5L PDK (365 Bhp) 05/2017>>
• Porsche Cayman 2.7L 981 2013-16
• Porsche Cayman S / GTS 3.4L 981 2013-16
• Porsche Cayman 718 2.0L Manual (300 Bhp)
• Porsche Cayman 718 2.0L PDK (300 Bhp)
• Porsche Cayman S 718 2.5L Manual (350 Bhp)
• Porsche Cayman S 718 2.5L PDK (350 Bhp)
• Porsche Cayman T 718 2.0L Manual (300 Bhp)
• Porsche Cayman T 718 2.0L PDK (300 Bhp)
• Porsche Cayman GTS 718 2.5L Manual (365 Bhp)
• Porsche Cayman GTS 718 2.5L PDK (365 Bhp)

Mounting points: 4
Position: Rear lower chassis / rear subframe area

During hard cornering, braking and acceleration, loads transferred through the suspension can cause a degree of movement or flex within the vehicle structure. The brace provides additional reinforcement between these mounting points, helping the rear suspension geometry remain more consistent under load.

The result is a more stable and predictable rear end, particularly during fast road driving, track days and other situations where the chassis is subjected to higher cornering loads.

What does the Ultra Racing rear lower brace do?

The suspension works most effectively when its mounting points remain stable.

As cornering forces increase, the chassis and subframe can experience small amounts of movement. Although this movement may be relatively minor, it can affect how accurately the suspension maintains its intended geometry.

The Ultra Racing rear lower brace links several important mounting points together, helping distribute loads across a wider section of the chassis.

This can help provide:

• Increased rear chassis rigidity
• Reduced movement around suspension mounting points
• More consistent rear suspension geometry
• Improved stability during hard cornering
• Sharper and more predictable handling response
• Improved driver feedback during enthusiastic driving

Why upgrade the Porsche 981 rear chassis?

The Porsche 981 Boxster and Cayman already have a highly capable chassis, but higher cornering loads can expose movement within suspension and subframe mounting areas.

This is particularly relevant where the vehicle has been fitted with:

• Performance tyres
• Wider wheels and tyres
• Sports suspension
• Lowering springs
• Coilover suspension
• Uprated anti-roll bars
• Track-focused suspension settings

These upgrades can increase the loads transmitted through the chassis.

Adding additional chassis reinforcement helps provide a more stable platform for the suspension to work from rather than allowing some of those forces to be absorbed through chassis movement.

How can the brace improve handling?

A suspension system is designed around specific geometry.

If the suspension mounting points move slightly under heavy loads, wheel alignment angles can also change dynamically. Additional chassis reinforcement helps reduce this movement.

Drivers may notice:

• More precise rear suspension response
• Improved stability during direction changes
• Greater confidence during high-speed cornering
• More predictable behaviour close to the car's handling limits
• Improved consistency during track driving
• Better feedback through the chassis

The difference is typically most noticeable during enthusiastic driving where higher cornering and braking forces are generated.

4-point chassis reinforcement

This brace uses a 4-point mounting arrangement.

Connecting four chassis or subframe mounting locations allows forces to be distributed across a larger structural area rather than concentrating loads at individual points.

This arrangement provides additional reinforcement across the rear underside of the vehicle while retaining a relatively simple bolt-on design.

Ultra Racing construction

Ultra Racing manufactures its chassis braces using steel tubing and reinforced mounting plates designed to provide high rigidity.

Ultra Racing states that its mounting brackets typically use approximately 4–5mm steel plate, while its hollow steel tubing is generally around 1.2–1.6mm thick depending on the application. The aim is to provide a rigid structure capable of maintaining its geometry under chassis load.

Please note: This product is a special order part and once ordered it cannot be cancelled or returned without our permission.