Audi B5 A4/S4/RS4 — Front Tubular Subframe — WAS-510
Our front subframe for the Audi B5 A4, S4, RS4, and Audi A6 C5 2.7T manual is the result of extensive CAD development, 3D scanning, and rigorous testing with CAD FEA (Finite Element Analysis) and real-world evaluations. This brand-new, rust-free subframe offers a significant upgrade over the OEM unit, combining increased stiffness with substantial weight reduction.
Key Features:
- Lightweight and Stiff: Weighs only 8.5 kg, offering a 7.5 kg (16 lbs) weight savings over the OEM subframe, improving overall vehicle performance.
- Premium Materials: Constructed from T45 tubing (BS4T45 to BS4T100) imported from the UK and S355 metal sheets, providing exceptional strength and durability.
- High-Quality Construction: All components are TIG welded for superior strength and longevity.
- Customizable Finish: Delivered painted (powder-coated) in black, with the option for any RAL color (+50 euro).
- Solid Mounts: Provides increased stiffness and additional mass reduction through solid mounts to the car body.
- OEM Compatibility: Bolts directly to the OEM car body with no modifications needed and is compatible with OEM wishbones.
What’s Included:
- Front subframe painted black
- Printed installation instructions
Compatible With:
- Audi A4 B5
- Audi S4 B5
- Audi RS4 B5
- Audi A6 C5 2.7T manual (Not compatible with V8 4.2L models)
Material Properties:
T45 is a unique, seamless carbon-manganese steel tube, known for its superior strength compared to Co-Mo 4130 tubing. Widely used in aerospace applications, including pilot and crew seats, it withstands high G forces without snapping or splitting, conforming to full aerospace specifications as laid down by British Standards.
- Tensile Strength: 700 – 900 MPa
- Yield Strength: 0.2% at 620 MPa minimum
- Hardness: 201 min – 262 max HB or 210 min – 275 max HV
OEM Part Replacements:
- 8D0399313BT
- 4B0399313DE
- 4B0399313BL
- 8D0399313BH
Notice: This subframe is sold for off-road, track, and racing applications only. Professional installation by a qualified and experienced workshop is strongly recommended.