Whiteline Rear Sway Bar 20mm Adjustable – 2008-2021 Subaru WRX/STI

Whiteline Rear Sway Bar 20mm Adjustable – 2008-2021 Subaru WRX/STI

Entry-Level Adjustable Rear Bar for the GR/GV/VA Platform
The Whiteline BSR49Z 20mm adjustable rear sway bar for the 2008-2021 Subaru WRX and STI is the entry-level option in Whiteline’s BSR49 family — a step up from OEM in diameter and stiffness, with adjustable positions for tuning, without the additional roll stiffness of the 22mm or 24mm variants. This is the correct choice for drivers who want improved rear roll control over stock without committing to a stiffer setup.

DETAILS

• 20mm adjustable rear sway bar for 2008-2021 Subaru WRX and STI
• Adjustable positions for roll stiffness tuning
• Hollow chromoly steel construction
• Includes mount bushings and hardware
• Step up from OEM without maximum stiffness commitment

Who the BSR49Z Is Right For
The 20mm BSR49Z is ideal for a daily driver WRX or STI where the priority is eliminating the sloppiest OEM body roll without creating a stiff, uncomfortable ride. It’s also a good starting point for owners new to sway bar tuning — get familiar with how the bar affects the car’s handling balance before stepping up to a larger diameter.

Adjustable Positions
Like the larger BSR49XZ and BSR49XXZ, the BSR49Z has adjustable end positions. Starting in the inner (softest) position and working out is the recommended approach for any sway bar upgrade.

The BSR49 Family
The BSR49, BSR49Z, BSR49XZ, and BSR49XXZ cover the GR/GV/VA WRX and STI at 20mm, 20mm adjustable, 22mm adjustable, and 24mm adjustable respectively. Choose the diameter that matches your intended use.

Why Choose Whiteline

Whiteline has been engineering suspension components from their facility in Australia since 1979. Every product in their catalog is developed with a clear goal: measurable improvement in handling, stability, and tyre contact. Whiteline’s polyurethane bushings, sway bars, control arms, and alignment correction kits are engineered using finite element analysis and validated on track before they reach the market. Their components are direct-fit, bolt-on solutions designed for enthusiasts who want real performance gains without fabrication or custom work.

The RallySport Take

The correct starting sway bar for GR/GV/VA WRX and STI owners who want roll control improvement without maximum stiffness. Adjustable for fine-tuning, direct bolt-on. Installation is a straightforward bar swap — remove the OEM bar, install the Whiteline unit with the provided polyurethane mount bushings, connect the endlinks. Start in the middle adjustment position and move from there. Adjustable endlinks are a worthwhile companion purchase if the car has been lowered, ensuring the bar operates at zero preload at the new ride height.

What’s in the Box

• 20mm adjustable rear sway bar for 2008-2021 Subaru WRX and STI
• Adjustable positions for roll stiffness tuning
• Hollow chromoly steel construction
• Includes mount bushings and hardware
• Step up from OEM without maximum stiffness commitment

Fitment