Torsion Bars

Sway-A-Way torsion bars are engineered as a direct replacement for the original front torsion bars and are available in a range of rate options from 19 mm through to 24 mm, allowing the suspension setup to be matched to the intended use of the vehicle.
SET OF 2, One pair is required per vehicle.

Fits:
Porsche 911: 1965 through 1989
Porsche 912: 1965 through 1969
Porsche 930 (Turbo): 1975 through 1989

Choose from the following torsion-bar rates: 19 mm,  20 mm,  21 mm,  22 mm, 23 mm  or 24 mm.
The different rates allow the front suspension setup to be tailored to suit anything from a standard-style road car through to fast-road, autocross and competition applications.

Product Information

High-performance Sway-A-Way tubular front torsion bar set for classic Porsche 911 models. Designed as a direct replacement and performance upgrade for the factory front torsion bars, these bars allow you to select the spring rate that best matches the vehicle's intended use, suspension specification and handling requirements.

 Unlike conventional solid torsion bars, the tubular / hollow construction is designed to achieve the required torsional spring rate while reducing unnecessary component weight. This provides an excellent strength-to-weight solution for performance-focused Porsche suspension systems.

Sway-A-Way torsion bars are manufactured from high-strength 4340 alloy steel, a material widely used where excellent fatigue resistance and strength under repeated torsional loading are required.

The bars are precision manufactured, heat treated and finished for durability, helping provide a consistent spring characteristic during demanding road and track use. Sway-A-Way product information specifies centreless-ground alloy-steel construction, heat treatment and protective coating on its Porsche torsion bars.

Choosing the Correct Torsion Bar Rate

The torsion bar acts as the spring in the classic Porsche 911 suspension system.
Increasing the torsion-bar rate increases suspension stiffness.

This can provide:
•  Reduced body roll
•  Sharper steering response
•  Improved control during aggressive cornering
•  Reduced suspension movement under load
•  Better support for performance tyres
•  Improved chassis response on track.

However, increasing torsion-bar stiffness also changes ride quality and the overall balance of the chassis.

 19 mm

A softer option suited to cars where road comfort and near-standard suspension behaviour are priorities.

Ideal for:
•   Standard or lightly modified cars
•   Road use Restoration projects
•   Drivers wanting compliant suspension behaviour

 20 mm

A mild performance increase that offers a useful step toward sharper handling without moving too far away from road-oriented suspension characteristics.

Ideal for:
•   Fast-road cars
•   Uprated road suspension
•   Weekend sports cars
•   Mild performance builds

Installation & Performance Notes:
•  Balanced Handling: When upgrading the front bars to 20mm, it is highly recommended to also upgrade the rear torsion bars to maintain the 911’s neutral handling balance. Pairing 20mm front bars with 26mm or 27mm rear bars is a common "sport" configuration.
•  Indexing: These bars utilize the factory splined ends. Correct indexing (clocking) during installation is critical to achieving the proper stance. Document your original bar's orientation before removal to simplify the setup of your new ride height.
•  Maintenance: Thoroughly clean the female splines in the A-arms and adjustment caps. Apply a high-quality waterproof grease to the splines during assembly to prevent future seizing and "creaking" during cornering.


 21 mm

A more noticeable performance upgrade providing increased front-end support and reduced body movement.

Ideal for:
•  Fast-road driving
•  Autocross
•  Dual road/track use
•  Performance suspension builds

 A 21 mm effective rate represents a substantial increase in stiffness compared with a standard 19 mm front torsion-bar rate.

Performance & Installation Notes:
•  System Balance: To prevent excessive understeer, 21mm front bars should generally be paired with upgraded rear torsion bars (typically 27mm or 28mm) to keep the 911’s handling neutral.
•  Damping Requirements: Because the spring rate is significantly higher than stock, standard comfort-valved shocks may be overwhelmed. Performance-valved dampers (such as Bilstein B8 or similar) are highly recommended.
•  Spline Care: Always clean the female splines in the A-arms and adjustment caps before installation. Use high-quality waterproof grease on the splines to prevent future seizing and ensure quiet operation.

 22 mm

A performance-focused option suitable for cars using uprated dampers, tyres and complementary rear suspension upgrades.

Ideal for:
•  Aggressive fast-road use
•  Track days
•  Lightweight builds

Installation & Setup Notes
•  Weight Benefit: The tubular design reduces unsprung mass at the front of the vehicle, allowing the suspension to react more quickly to road imperfections compared to a solid bar of the same rate.
•   Spline Care: These bars feature factory-style splined ends. Ensure the female splines in the A-arms are clean and lubricated with a high-pressure waterproof grease during assembly to prevent "creaking."
•   Indexing: Due to the 22mm diameter, indexing is sensitive. Document your original bar position to ensure you can accurately set your desired ride height (factory or "Euro" spec).
 
 23 mm

A significantly stiffer option intended primarily for serious performance and competition applications.

Ideal for:
•  Track cars
•  Autocross
•  Competition builds
•  RSR-style projects
•  Cars using competition-spec dampers and rear torsion bars

The 23 mm tubular version is described by X-Sway as a competition-oriented front torsion bar with substantially increased rate over a stock 19 mm setup.

Performance & Installation Notes:
•  Balanced Setup: At a 23mm front rate, you must upgrade your rear torsion bars (typically to 30mm or 31mm) to maintain the 911’s handling balance. Using these with stock rear bars will result in severe understeer.
•   Damping Requirements: This spring rate requires aggressive damping. We recommend competition-valved struts (such as Bilstein RSR-spec or custom-valved dampers) to prevent the front end from feeling "bouncy."
•   Spline Maintenance: Clean and inspect the female splines in your A-arms and adjustment caps. Apply a high-quality waterproof grease to the splines during installation to ensure quiet operation and prevent seizing.
•   Indexing: Because these bars are so stiff, indexing is extremely sensitive. A single spline adjustment will move the ride height significantly; document your starting position carefully.

 24 mm

The stiffest option in this range, intended for highly developed suspension setups where maximum front spring control is required.

Ideal for:
•  Dedicated track cars
•  Motorsport applications
•  Lightweight competition builds
•  Cars with suitably matched rear spring rates and dampers




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

FT18

The product you are viewing cross references to these numbers

High-performance Sway-A-Way hollow rear torsion bar set for Porsche 911 models equipped with the G50 transmission from 1987 to 1989. Available in 27 mm, 28 mm and 29 mm rates. Designed as a direct performance replacement for the original rear torsion bars, these tubular bars provide increased rear suspension control while reducing weight compared with equivalent solid torsion bars.
SET OF 2, One pair is required per vehicle

Fits:
Porsche 911 1987-1989 3.2L G50
Porsche 911 1978-1989 3.3L Turbo (930)

Always confirm that your vehicle uses the G50 transmission and corresponding rear suspension configuration before ordering.

The tubular construction is engineered so that the hollow bar provides the same effective spring rate as the equivalent solid-diameter torsion bar, while reducing the amount of material and therefore overall component weight.

Sway-A-Way torsion bars are manufactured from high-strength, heat-treated alloy steel. The bars are precision centreless ground for consistent dimensions and spring characteristics, then finished with a protective powder coating to help resist corrosion.

Available Torsion Bar Rates

 27 mm - Fast-road and occasional track use

The 27 mm tubular rear torsion bar provides a useful performance increase while remaining a sensible option for cars that see regular road use. Sway-A-Way identifies the tubular 27 mm bar as having the stiffness of an equivalent solid 27 mm torsion bar while providing a useful weight reduction.

Recommended for:
•  Fast-road Porsche 911s
•  Uprated road suspension
•  Occasional track-day us
•  Cars using uprated dampers and front torsion bars

The 27 mm option provides greater rear suspension support without immediately moving to one of the highest rates in the range.

Technical Setup & Performance Notes:
•  Unsprung Weight Benefits: Because the tubular bar is lighter, the suspension has less inertia. This allows your dampers to work more efficiently, resulting in better mechanical grip on rougher track surfaces or uneven canyon roads.
•  Matched Balancing: A 27mm rear rate is a significant jump. To maintain the 911’s famous handling balance, it is highly recommended to pair these with 21mm or 22mm front torsion bars.
•  Damping Requirements: Standard shocks may struggle with the increased "snap" of a 27mm rate. Custom-valved Bilstein or Koni dampers are recommended to properly control the rebound.
•  Spline Care: During installation, apply a generous amount of waterproof anti-seize grease to the splines. Because tubular bars are more resonant than solid ones, proper lubrication is essential to prevent "creaking" or "clunking" sounds. 

 28 mm - Fast-road / track-day performance (not recommended for off-road use)

The 28 mm tubular rear torsion bar provides a further increase in spring rate, offering stronger control of rear suspension movement during hard acceleration and cornering.

Recommended for:
•  Aggressive fast-road use
•  Road and track-day cars
•  Autocross
•  Performance builds using modern high-grip tyres
•  Cars with matched performance dampers.

This is a strong middle option for drivers wanting a more focused chassis while retaining some flexibility for road use.

 29 mm Track-focused and competition-oriented applications (not recommended for off-road use)

The 29 mm tubular rear torsion bar is the firmest of these three G50 options and is aimed at more serious performance-oriented suspension setups.

Recommended for:
•  Track-focused Porsche 911s
•  Competition-inspired builds
•  Autocross
•  Lightweight cars
•  High-grip tyre setups
•  Cars with appropriately matched front torsion bars and performance dampers

The increased rear spring rate provides greater resistance to squat and roll but should be combined with a balanced overall suspension package.

Why Upgrade the Rear Torsion Bars?

The classic Porsche 911 suspension uses torsion bars as its primary springs. As suspension load increases, the torsion bar twists along its length. The resistance to this twisting action determines the effective spring rate.

Increasing the torsion-bar rate can provide:
•  Reduced body roll
•  Reduced rear-end squat during acceleration
•  Improved suspension control
•  More immediate chassis response
•  Greater stability during fast cornering
•  Better support for high-grip modern tyres
•  Improved control during track use
•  Improved balance when combined with complementary front suspension upgrades.

The larger the effective torsion-bar diameter, the greater the spring rate.

Tubular / Hollow Construction

Sway-A-Way tubular torsion bars are designed to reduce weight without sacrificing the desired spring rate.

The internal diameter of the hollow bar is engineered so that its torsional stiffness corresponds to the stated solid-bar rate.

This means a 27 mm tubular-rate bar is designed to provide the spring characteristics associated with a 27 mm solid torsion bar, rather than simply being a hollow 27 mm tube with a significantly softer rate.

This construction provides an attractive combination of:
•  High torsional strength
•  Reduced component weight
•  Consistent spring rate
•  Durable performance
•  Motorsport-oriented engineering.

For Porsche owners looking to reduce unnecessary weight while upgrading suspension performance, the tubular design provides a useful advantage over conventional solid bars.

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

RT21

The product you are viewing cross references to these numbers

Plated & Plugged Hollow Torsion Bars.
Plated/Plugged 26mm, PAIR



Fits:
Porsche 911/912/930 1965-86
Porsche 356 A / 356 B / 356 Pre-A, C And CS Read Notes* (1948-65)

Our Plated & Plugged Hollow torsion bars are the best available. The ends are plugged to prevent moisture entry that rots ordinary hollow bars from the inside out. The entire bar is zinc plated for superior protection.

Excellent quality control means proper spline fit and spring-rate consistency bar-to-bar. Inferior quality competing bars fail on all counts.

• Hollow, light weight
• Plated & Plugged
• Consistent spring rate
• Great spline fit

Upgrade Hollow bars provide a nice weight savings over equivalent spring rate solid bars, especially true of the heavier rear bars. This is a great way to trim extra pounds from the back of your car.

* The size given is a solid-bar-equivalent. Actual hollow bar measures about. 5mm larger.

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

1-PP911R26

The product you are viewing cross references to these numbers

Plated & Plugged Hollow Torsion Bars - REAR
Plated/Plugged 29mm, PAIR



Fits:
For G50 Transmission
Porsche 911/912/930 1987-89


Our Plated & Plugged Hollow torsion bars are the best available. The ends are plugged to prevent moisture entry that rots ordinary hollow bars from the inside out. The entire bar is zinc plated for superior protection.

Excellent quality control means proper spline fit and spring-rate consistency bar-to-bar. Inferior quality competing bars fail on all counts.

• Hollow, light weight
• Plated & Plugged
• Consistent spring rate
• Great spline fit

Upgrade Hollow bars provide a nice weight savings over equivalent spring rate solid bars, especially true of the heavier rear bars. This is a great way to trim extra pounds from the back of your car.

* The size given is a solid-bar-equivalent. Actual hollow bar measures about. 5mm larger.

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

1-PP911RT29

The product you are viewing cross references to these numbers

Plated & Plugged Hollow Torsion Bars. - REAR
Plated/Plugged 27mm, PAIR



Fits:
Porsche 911/912/930 1965-86
Porsche 356 A / 356 B / 356 Pre-A, C And CS Read Notes* (1948-65)

Our Plated & Plugged Hollow torsion bars are the best available. The ends are plugged to prevent moisture entry that rots ordinary hollow bars from the inside out. The entire bar is zinc plated for superior protection.

Excellent quality control means proper spline fit and spring-rate consistency bar-to-bar. Inferior quality competing bars fail on all counts.

• Hollow, light weight
• Plated & Plugged
• Consistent spring rate
• Great spline fit

Upgrade Hollow bars provide a nice weight savings over equivalent spring rate solid bars, especially true of the heavier rear bars. This is a great way to trim extra pounds from the back of your car.

* The size given is a solid-bar-equivalent. Actual hollow bar measures about. 5mm larger.

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

1-PP911R27

The product you are viewing cross references to these numbers

QuickChange™ Torsion Bars, FRONT
Sold per kit, 1 kit req'd per car.

Fits:
Porsche 911/912/930 1965-89
Porsche 914 1970-76

QuickChange Torsion Bars are Plated & Plugged and include a female threaded end that you can engage with a bolt to use as a handle for easier extraction / insertion.

Use the rears bars in combination with our QuickChange™ Spring Plate products for fast torsion bar swapping and re-indexing. QuickChange™ Torsion Bars can be extracted through the QuickChange™ Spring Plate without removing any bolts. Alignment settings are maintained. You don't even need to remove the wheel from the car. Changing torsion bars is a 5 minute per side operation!

A QuickChange™ Insert is available separately for converting your existing hollow torsion bars.

QuickChange™ Torsion Bars make it easy to dislodge a stuck bar, and thereby offer benefits even when used on the front and with factory spring plates (factory spring do not allow the bars to be extracted without removing the plates).

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

209202

The product you are viewing cross references to these numbers

QuickChange™ Torsion Bars, REAR
Sold per kit, 1 kit req'd per car.



Fits:
for G50 Transmission
Porsche 911 / 930 1987-89

QuickChange Torsion Bars are Plated & Plugged and include a female threaded end that you can engage with a bolt to use as a handle for easier extraction / insertion.

Use the rears bars in combination with our QuickChange™ Spring Plate products for fast torsion bar swapping and re-indexing. QuickChange™ Torsion Bars can be extracted through the QuickChange™ Spring Plate without removing any bolts. Alignment settings are maintained. You don't even need to remove the wheel from the car. Changing torsion bars is a 5 minute per side operation!

A QuickChange™ Insert is available separately for converting your existing hollow torsion bars.

QuickChange™ Torsion Bars make it easy to dislodge a stuck bar, and thereby offer benefits even when used on the front and with factory spring plates (factory spring do not allow the bars to be extracted without removing the plates).

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

21021

The product you are viewing cross references to these numbers

High-performance Sway-A-Way solid front torsion bars for classic Porsche 911 models. Designed as direct replacements for the original front torsion bars, these performance bars allow you to select the front spring rate that best suits your Porsche, from a factory-style replacement through to a considerably firmer competition suspension setup.
SET OF 2, One pair is required per vehicle.

Fits:
Porsche 911: 1965 through 1989 
Porsche 912: 1965 through 1969
Porsche 930 (Turbo): 1975 through 1989 (Verify diameter requirement; some Turbos utilized larger bars for track use)

Always confirm the required torsion-bar diameter and vehicle suspension specification before ordering.

Choose from the following torsion-bar rates: 18 mm, 19 mm,  20 mm,  21 mm,  22 mm, 23 mm  24 mm, 25 mm or 26 mm.
With sizes ranging from the factory-style 19 mm rate through to the competition-focused 26 mm option, this Sway-A-Way range allows the front suspension to be tailored for standard road use, fast-road driving, track days or dedicated motorsport applications.

Product Information

The classic Porsche 911 uses torsion bars as its suspension springs. As the front suspension moves, the torsion bar twists along its axis and provides the resistance necessary to support and control the vehicle.

Increasing the torsion-bar diameter increases the spring rate, providing greater resistance to suspension movement. This can help reduce front-end dive under braking, limit body roll during cornering and provide a more immediate chassis response.

Manufactured using solid high-strength 4340 alloy steel, Sway-A-Way torsion bars are designed to withstand repeated torsional loading while providing consistent spring characteristics.

Choosing the Correct Torsion Bar Rate

 19 mm Solid (OEM Standard Diameter)

The 19 mm torsion bar is the factory-style option within the range and is ideal for owners looking to replace tired original torsion bars while maintaining near-standard suspension characteristics. Note: Engineered as a direct-fit replacement for the front independent suspension.

Recommended for:
•  Standard road cars
•  Original-specification restorations
•  Touring use
•  Cars where ride comfort is important
•  Owners seeking factory-style front suspension behaviour

This is the natural choice where maintaining the classic Porsche road feel is the priority.

Installation & Setup Notes:
•   Indexing & Ride Height: These bars utilize the factory splined ends. Correct indexing (clocking) during installation is critical to achieving the proper stance. Small adjustments at the splines result in significant changes at the wheel.
•   Grease: Always apply a high-quality Moly-based or waterproof grease to the splines before sliding the bars into the A-arms and adjustment caps to prevent future seizing and "creaking" during cornering.
•   Upgrade Path: If you are preparing your 911 for competitive autocross or track days, consider stepping up to a 21mm or 22mm bar. This 19mm bar is specifically optimized for street comfort and original factory handling dynamics.

  20 mm Solid (Performance Upgrade)

The 20 mm torsion bar provides a mild increase in front spring rate compared with the standard 19 mm setup. It offers sharper suspension response and reduced front-end movement without moving too far away from road-oriented ride characteristics. 
Spring Rate: Higher than OEM (Approximately 23% stiffer than 19mm bars) 
Note: A popular choice for Carrera models looking to sharpen front-end response or for early "long-hood" cars being prepared for rally or fast road use.

Recommended for:
•  Fast-road cars
•  Mild performance upgrades
•  Weekend sports cars
•  Uprated road suspension
•  Cars using performance dampers and tyres

A good choice for owners wanting a noticeable but relatively restrained suspension upgrade.

Installation & Performance Notes:
•  Balanced Handling: When increasing the front bar diameter to 20mm, it is highly recommended to also upgrade the rear torsion bars (typically to 26mm or 27mm) to maintain the 911’s neutral handling balance and prevent induced understeer.
•  Spline Maintenance: Thoroughly clean the female splines in the A-arms and adjustment caps. Use a high-pressure waterproof grease on the splines during assembly to prevent "popping" noises and ensure easy adjustment in the future.
•  Indexing: Because these bars use the factory spline count, small changes in indexing result in significant ride height shifts. We recommend documenting your original bar's orientation before removal.

  21 mm Solid  (Performance Upgrade)

The 21 mm torsion bar provides a more significant increase in front spring rate and is well suited to performance-oriented road and occasional track cars. Spring Rate: Stiffer than OEM (Approximately 45–50% stiffer than 19mm bars).
Note: This is a common performance upgrade for Carrera 3.2 and SC models to improve front-end bite and overall chassis responsiveness.

Recommended for:
•  Fast-road Porsche 911s
•  Road and track-day cars
•  Autocross Carrera and SC performance builds
•  Cars using uprated dampers
•  Modern high-grip tyre packages

The increased rate provides stronger resistance to front suspension compression during braking and cornering.

Installation & Performance Notes:
•  Chassis Balance: Upgrading to 21mm front bars typically requires a corresponding upgrade to the rear torsion bars (often to 27mm or 28mm) to maintain the 911's intended handling characteristics and prevent excessive understeer.
•  Shock Matching: Due to the significantly increased spring rate, factory comfort shocks will likely be under-damped. For best results, pair these with performance-valved shocks (such as Bilstein Clubman or Koni Sport).
•  Indexing: Document your factory bar indexing before removal. Because of the high spring rate, even a one-spline difference in "clocking" will result in a dramatic change in ride height.

 22 mm Solid

The 22 mm solid torsion bar moves further toward a track-focused suspension setup. It provides increased front-end support and reduced body movement, making it suitable for cars where handling response is prioritised over standard road comfort. Spring Rate: Stock Equivalent. Note: While 22mm is typically a performance diameter, this SKU is specifically manufactured to provide a factory-style ride quality.

Recommended for:
•  Aggressive fast-road use
•  Frequent track days
•  Autocross
•  Lightweight performance cars
•  Uprated dampers
•  Complementary rear torsion-bar upgrades

Installation & Setup Notes:
•  Spline Fitment: These bars utilize the factory-style splined ends. Ensure the female splines in your A-arms and adjustment caps are thoroughly cleaned and free of debris before installation.
•  Lubrication: Use a high-quality, high-pressure waterproof grease on the splines during assembly to prevent "popping" or "creaking" and to ensure easy removal in the future.
•  Indexing: Because small changes in spline "clocking" result in significant ride height shifts, document your original bar's orientation before removal to simplify the setup of your new stance. 

 23 mm Solid  (Competition Grade)

The 23 mm solid torsion bar is a substantial performance upgrade designed for aggressive road, track and competition applications. It provides considerably greater resistance to front-end dive and body roll than the factory-style 19 mm configuration. Spring Rate: Significantly higher than OEM (Approx. 110–120% stiffer than 19mm bars). Note: Ideal for 911s used in competitive track environments, autocross, or for owners who prefer a very firm, communicative chassis.

Recommended for:
•  Track-focused Porsche 911s
•  Motorsport-inspired build
•  Autocross
•  Competition applications
•  Cars using performance or competition dampers
•  High-grip tyre setup

 At this level, the complete front-to-rear suspension balance becomes particularly important.

Installation & Performance Notes:
•  Chassis Reinforcement: Because 23mm bars exert significantly more force on the chassis than factory bars, it is highly recommended to inspect—and potentially reinforce—the torsion bar mounting points and A-arm brackets.
•  System Balance: To maintain neutral handling, 23mm front bars must be paired with much stiffer rear bars (typically 30mm or 31mm). Failure to balance the rear will result in severe understeer.
•  Shock Damping: Standard or even "Sport" street shocks will be insufficient for this spring rate. Competition-valved dampers (such as Bilstein RSR or Custom Valved Koni) are necessary to control the oscillation of a 23mm bar.
•  Spline Care: Apply high-pressure waterproof grease to the splines during assembly to prevent "popping" noises and to ensure the bars do not seize in the A-arms.

  24 mm Solid

The 24 mm solid front torsion bar provides a high spring rate intended primarily for developed performance and competition suspension packages.

Recommended for:
•  Dedicated track cars
•  Competition Porsche 911s
•  Lightweight race builds
•  High-grip tyre applications
•  Cars with substantially uprated rear torsion bars
•  Competition-valved dampers

This size is most appropriate where chassis control takes priority over road comfort.

  25 mm Solid

The 25 mm solid torsion bar is a very high-rate front suspension option aimed at serious motorsport applications.

Recommended for:
•  Race-prepared Porsche 911s
•  Motorsport builds
•  High-downforce or high-grip cars
•  Competition suspension systems
•  Vehicles with appropriately matched rear spring rates

Professional suspension setup is strongly recommended at this level of spring stiffness.

  26 mm Solid

The 26 mm solid torsion bar represents the most aggressive option in this range. Designed for highly developed competition vehicles, it provides extremely high resistance to front suspension movement and should only be used as part of a properly engineered suspension package.

Recommended for:
•  Dedicated race cars
•  Motorsport applications
•  Highly developed track builds
•  Very high-grip suspension setups
•  Cars using competition-spec dampers
•  Vehicles with suitably matched rear torsion-bar rates

For typical road use, one of the smaller sizes will generally provide a more appropriate balance of suspension performance and compliance.


Why Upgrade Front Torsion Bars?

On a classic Porsche 911, the torsion bar performs the same fundamental function as a conventional coil spring. When the suspension moves, the bar twists. The resistance of the bar to this twisting movement determines the effective spring rate.

Increasing the torsion-bar diameter can provide:
•  Reduced front-end dive under braking
•  Reduced body roll Improved steering response
•  Greater suspension control
•  More immediate turn-in
•  Better support for performance tyres
•  Improved chassis response during track driving
•  Increased resistance to suspension compression

The larger the solid torsion-bar diameter, the greater the spring rate.

Solid Construction

These torsion bars use a traditional solid construction. Solid torsion bars are an excellent choice for owners who prioritise performance, durability and value over the weight saving provided by tubular alternatives.

Advantages include:
•  Proven construction
•  High torsional strength
•  Consistent spring behaviour
•  Excellent durability
•  Wide choice of spring rates
•  Competitive cost compared with hollow alternatives
•  Suitable for road and competition use

For customers primarily focused on achieving a specific spring rate rather than reducing suspension component weight, the solid Sway-A-Way range provides an excellent solution.

4340 Alloy Steel

Sway-A-Way uses high-strength 4340 alloy steel for its Porsche torsion bars. This material is particularly suitable for components subjected to repeated twisting loads because of its combination of strength and fatigue resistance.

The manufacturing process includes:
•  High-strength alloy-steel construction
•  Precision centreless grinding
•  Heat treatment
•  Shot peening
•  Controlled dimensions
•  Protective powder coating

These processes help provide predictable spring characteristics and long-term durability.

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

FS18

The product you are viewing cross references to these numbers

High-performance Sway-A-Way solid rear torsion bar set for Porsche 911 models equipped with the G50 transmission from 1987 to 1989. Available in 26 mm, 27 mm, 28 mm and 29 mm rates. Designed as a direct suspension upgrade, these solid torsion bars allow the rear spring rate of the classic Porsche 911 suspension to be increased without converting the vehicle to coil springs.
SET OF 2, One pair is required per vehicle

Fits:
Porsche 911 1987-1989 3.2L G50
Porsche 911 1978-1989 3.3L Turbo (930)

Always confirm that your vehicle uses the G50 transmission and corresponding rear suspension configuration before ordering.

Available in 26 mm, 27 mm, 28 mm and 29 mm diameters, the range provides several levels of rear suspension stiffness, from a relatively mild fast-road upgrade through to a much firmer track-focused setup.

Increasing the torsion-bar diameter raises the effective spring rate, helping reduce rear suspension movement, body roll and squat during acceleration. This can provide a more controlled and responsive chassis, particularly when combined with suitable front torsion bars, dampers, anti-roll bars and performance tyres.

The solid construction offers a straightforward, durable solution for owners looking to upgrade the suspension without the additional cost associated with lightweight hollow torsion bars.

Available Torsion Bar Rates

 26 mm Solid (performance street / light-track upgrade)

The 26 mm solid rear torsion bar is the mildest performance option in this range. It provides increased rear suspension support while remaining particularly suitable for a road-focused Porsche where improved chassis control is wanted without moving directly to a substantially stiffer competition setup.

Recommended for:
•  Performance road cars
•  Fast-road use
•  Mild suspension upgrades
•  Uprated dampers
•  Cars using modern performance tyres
•  Occasional track-day use

Installation & Performance Notes:
•  System Balance: Suspension tuning is about ratios. If you increase the rear bar size to 26mm, you should ensure your front torsion bars are matched accordingly (typically paired with 21mm or 22mm front bars) to prevent excessive oversteer.
•  Indexing and Ride Height: Setting the ride height on a 911 is done by "clocking" the splines on the torsion bar. Because the 26mm bar is stiffer than stock, the car will sit higher than it did with the factory bars if indexed at the same angle.
•  Bushings: This is the perfect time to inspect or replace your rear spring plate bushings. High-performance bars work best when paired with fresh polyurethane or Neatrix bushings to eliminate "stiction."
•  Lubrication: Clean the splines thoroughly and apply a generous amount of waterproof, anti-seize grease to both ends of the bar. This prevents the bars from "creaking" and ensures they won't seize in the tube for future adjustments.

 27 mm Solid

The 27 mm solid rear torsion bar provides a more noticeable increase in rear spring rate. It is a strong choice for drivers looking for a more responsive chassis while retaining versatility for both road and occasional circuit use.

Recommended for:
•  Fast-road Porsche 911s
•  Clubsport-style builds
•  Road and track-day cars
•  Autocross
•  Performance suspension packages
•  Cars using uprated front torsion bars and dampers

The 27 mm Sway-A-Way bar is specifically positioned as a high-performance rear suspension upgrade for Porsche 911 applications.

Technical Setup & Performance Notes:
•  Chassis Balance: A 27mm rear bar is quite stiff. It is almost always paired with 22mm front torsion bars to maintain a neutral handling balance. Pairing 27mm rears with stock small-diameter fronts may result in excessive oversteer (the tail sliding out).
•  Damping Requirements: Due to the higher spring rate, you will likely need to upgrade to "Sport" valved dampers (such as Bilstein Clubsport or custom-valved Koni) to control the faster rebound speeds of these bars.
•  Ride Quality: While still streetable, the 27mm bar will transmit more road vibration than stock. It is perfect for canyon carving and track use but may feel firm over city potholes.
•  Weight Comparison: If choosing the Tubular option, you effectively reduce "unsprung" weight. This allows the suspension to react faster to bumps, keeping the tire in better contact with the pavement compared to a heavier solid bar of the same rate. 

  28 mm Solid  (competition / heavy performance)

The 28 mm solid rear torsion bar moves further toward a dedicated performance suspension setup. The increased spring rate helps provide stronger resistance to suspension compression and body movement during aggressive cornering and acceleration.

Recommended for:
•  Aggressive fast-road use
•  Regular track days
•  Autocross
•  Lightweight performance builds
•  High-grip tyre packages
•  Cars with appropriately matched performance dampers

A 28 mm rear bar should be considered as part of the complete suspension package rather than as an isolated upgrade.

Critical Installation & Performance Notes:
•  Chassis Balance: A 28mm rear bar is extremely stiff. To avoid dangerous snap-oversteer, these must be paired with upgraded front torsion bars (typically 23mm or 24mm fronts).
•  Damping Requirements: Standard street shocks (like Bilstein HD) will be completely overwhelmed by this spring rate. You must use custom-valved racing dampers with high rebound control to prevent the car from bouncing uncontrollably over bumps.
•  Mounting & Bushings: At this performance level, factory rubber bushings will deflect excessively. We highly recommend upgrading to spherical bearings or bronze bushings to ensure the torsion bar can move freely without binding.
•  Ride Quality: This setup is very firm. While technically street-legal, it is optimized for smooth race tracks and high-speed canyon carving. You will feel every imperfection in the road surface. 

 29 mm Solid  (full competition grade)

The 29 mm solid rear torsion bar is the stiffest option in this range and is aimed primarily at more serious track and competition-oriented builds.

It provides substantial rear roll stiffness and resistance to acceleration squat, making it suitable for cars where maximum suspension control takes priority over standard road comfort.

The 29 mm solid rear bar is a competition-focused option for highly developed performance applications.

Recommended for:
•  Track-focused Porsche 911s
•  Competition builds
•  Motorsport applications
•  High-grip tyre setups
•  Lightweight race cars
•  Cars using matched competition dampers
•  Vehicles with complementary front spring rates

Critical Competition Notes:
•  Chassis Balance: A 29mm rear bar is exceptionally rigid. To prevent dangerous snap-oversteer, it is mandatory to pair these with appropriately stiff front bars (typically 23mm to 24mm).
•  Damping Requirements: Standard or "Sport" street shocks are completely insufficient for this rate. You must use professional, custom-valved racing dampers with significant rebound control to manage the energy of a 29mm bar.
•  Bushings & Bearings: We strongly recommend replacing rubber bushings with spherical bearings or high-durometer bronze bushings. Factory rubber will simply collapse under the forces transmitted by a 29mm bar, leading to unpredictable handling.
•  Ride Quality: This setup is not recommended for street use. The ride will be extremely harsh, and the high spring rate can put significant stress on factory chassis mounting points if they are not reinforced.


Why Upgrade the Rear Torsion Bars?

The classic Porsche 911 uses torsion bars as its suspension springs.

Rather than compressing like a conventional coil spring, the torsion bar twists along its axis as the wheel moves through its suspension travel.

Increasing the torsion-bar diameter increases resistance to twisting and therefore raises the suspension spring rate.

Benefits of an appropriately selected larger rear torsion bar can include:
•  Reduced body roll
•  Reduced rear-end squat during acceleration
•  Improved chassis response
•  Increased suspension control
•  Better support for modern performance tyres
•  Improved stability during fast cornering
•  More predictable suspension movement on track.

Solid Construction

 These Sway-A-Way torsion bars use a conventional solid construction.

Solid torsion bars offer several advantages:
•  Simple and proven construction
•  Excellent torsional strength
•  Consistent spring characteristics
•  Durable performance
•  Competitive pricing compared with tubular alternatives
•  Suitable for both road and competition use

For customers primarily interested in increasing spring rate rather than reducing suspension component weight, the solid-bar range offers an excellent performance solution.

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

RS21

The product you are viewing cross references to these numbers