Torsion Bar Set - Porsche 911 - 29 MM

The solid 29mm rear torsion bar is a professional competition-grade suspension component. Among the stiffest solid bars available for the torsion-bar-equipped Porsche 911, the SKU 2129 is designed specifically for dedicated track cars, heavy RSR recreations, and high-downforce racing applications. This setup provides the extreme roll resistance necessary to maintain chassis stability when using wide racing slicks and aggressive aerodynamic elements.

Performance & Fitment

Application: Rear Torsion Bar Set

Diameter: 29mm (Full Competition Grade)

Type: Solid

Spring Rate: Extreme upgrade. This bar provides a massive increase in stiffness—approximately 215% stiffer than the factory 24.1mm bars found on many mid-year 911s.

• Porsche 911: 1965 through 1989

• Porsche 912: 1965 through 1969

• Porsche 930 (Turbo): 1975 through 1989

• Fitment Note: These are direct-fit replacements for the factory rear bars, though they are intended for vehicles with significant chassis and damping modifications.

Premium Construction

• Material: Forged from solid, heat-treated aircraft-grade alloy steel. At this diameter, the material must handle immense torsional loads without permanent deformation.

• Manufacturing: Centerless ground to a precision 29mm diameter. This ensures a perfectly uniform spring rate and a flawless surface finish, which is critical to preventing the stress fractures that can occur under high-frequency racing vibrations.

• Heat Treatment: Through-hardened and shot-peened to ensure the bar maintains its "memory" and specified ride height throughout grueling endurance races.

• Finish: Industrial-grade powder coating protects the alloy steel from the elements and track debris.

⚠️ 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.

What’s Included

• One torsion bar set

Warranty

Backed by a 1-year warranty for peace of mind.

Availability: 3 in stock – Available for Back Order