Technically modern design combined with a high quality production process, these attributes characterise the AC Schnitzer AC4 Flowforming wheel generation, which is launched in the sizes 8.5J x 20" and 9.5J x 20", in the colour variants BiColor Silver/Black and Black.
The circumferential undercut reflects the high technical standard of the AC4 Flowforming rim. This is because this design element can actually only be realised if it is machined out of a solid material, such as is required in the forging process, as it is located behind the spokes. The undercut of the AC4 Flowforming rims is particularly visible on the BiColor version, as it brings out the high-quality aluminium with its silver surface.
Only high-quality aluminium alloys are used. The material is additionally heat-treated in the production process, which results in higher strength and simultaneous weight reduction.
Material samples during the production process guarantee the constant and high quality of the material.
Due to the production process, the new AC4 Flowforming rims are lighter than conventionally cast alloy rims and this is measurable: the 8.5J x 20" weighs just 11 kg and the 9.5J x 20" rim also weighs only 11.9 kg.
The flowforming process is one of the most advanced manufacturing technologies in wheel industry. In this production process, after the actual aluminium casting, the raw product is further processed by rolling it out. This step serves to compress the metal, which guarantees greater stability and impact resistance of the rim.
On the other hand, the improved stability also allows the design of the wheels to be more filigree, as the wall thicknesses can be significantly thinner compared to conventionally manufactured rims.
In this process, the wheel is first primed, then completely painted. A two-layer clear coat is then applied, consisting of a polyester primer and the acrylic clear coat.
Test Procedures / Safety
After their design, the first sample rims are manufactured under real production conditions. These must undergo a multitude of tests. Among other things, the strength is tested. The "rim life" is simulated in the bending circumferential test. Every AC Schnitzer rim must withstand this intact in order to be allowed to be produced and sold at all.
This is followed by vehicle-specific tests, including test installations with check of unobstructed movement and driving tests on public roads and on race tracks. Only after these procedures our rims receive their homologation, i.e. the approval to be used in road traffic.
Wheels are safety-relevant components. Therefore, they are checked and tested with the greatest care. This starts with the first chemical material tests and ends with hard testing machine endurance runs:
- § 30 StVZO wheel guideline
- ECE R124
- Bending-rotation tests
- 90° impact test
- unwinding tests
Scope of delivery:
- rim AC4 Flowforming Black
- specific hub cover
- homologation certificate
- optional vehicle- and rim-specific mounting and fastening material
- care instructions
Uniqueness of the AC4 Flowforming Wheels:
- developed exclusively for BMW vehicles
- lasered original AC Schnitzer logo
- open design in Black, giving a clear view to the brakes
- engineered in Germany
- compatible with standard RDC system
- also available as a complete wheel
- Warranty 2 years
- production monitored according to ISO standard
- Black, optionally also in BiColor Silver/Black
- KDS mount for wheel alignment according to BMW specification is available
- Spacers/mounting package for the best possible position in the wheel arch (to be ordered separately)
- Assembly package vehicle specific optional