Description
Upgrade your BMW B58-powered G-Series with the ARM Motorsports G20 B58 4" Intake, engineered to dramatically increase airflow to the turbocharger while improving throttle response, turbo spool, power delivery, and induction sound. Unlike standard B58 intake systems, the ARM G20 B58 Intake features a massive 4-inch diameter throughout the entire intake path, making it one of the largest B58 intake solutions available for the G-Series platform.
The larger 4-inch bore significantly reduces intake restriction, allowing the turbocharger to draw in more air with less resistance. This can contribute to faster turbo spool, sharper throttle response, improved airflow, and increased power and torque, particularly on tuned B58 engines. The ARM G20 B58 Intake also produces a substantial change in engine sound, making turbo spool much more noticeable during acceleration and creating an audible charge-air venting sound when lifting off the throttle.
Key Features
- Massive 4-inch diameter throughout the intake system
- Increased airflow to the B58 turbocharger
- Increased power and torque potential
- Faster turbo spool
- Sharper throttle response
- Reduced intake restriction
- Significantly increased turbocharger induction sound
- Audible charge-air venting on throttle lift
- Designed for tuned B58 applications
- Connects directly to the OEM turbo inlet
- T6061 aluminum MAF pipe
- Six-layer reinforced silicone coupler
- Aluminum heat shield for improved protection from engine heat
- Wrinkle-black aluminum heat shield cover
- Precision CNC-machined MAF flange
- High-flow inverted air filter design
- 186 cubic inches of filter surface area
Construction and Performance
The ARM G20 B58 Intake uses an inverted air filter design with an impressive 186 cubic inches of surface area. Combined with ARM Motorsports' multimedia filter material, the system is designed to provide excellent airflow while maintaining effective filtration to support B58 engine builds across a wide range of power levels.
The intake filter is protected from excessive engine-bay heat by an aluminum heat shield surrounding the filter. The kit also includes an aluminum heat shield cover finished in matching wrinkle black for additional protection and a clean appearance within the G-Series engine bay.
At the heart of the system is a T6061 aluminum MAF pipe featuring a full 4-inch diameter throughout. The large-diameter pipe is designed to maximize airflow toward the B58 turbo inlet, helping prevent the intake system from becoming an airflow restriction as engine power increases. A precision CNC-machined MAF flange provides a precise, secure fit for the factory MAF sensor and is secured using the included bolts.
The MAF pipe connects to the B58 turbo inlet using a 4-inch, six-layer reinforced silicone coupler, providing a tight and leak-resistant connection. The ARM G20 B58 Intake is specifically designed to connect to the OEM turbo inlet.
By opening up the airflow path compared with the restrictive factory intake system, the ARM G20 B58 Intake is designed to help unlock the B58's power potential while delivering faster turbo spool and sharper throttle response. The larger intake also transforms the character of the B58 engine, producing significantly more turbocharger sound during acceleration and an aggressive blow-off or charge-air venting sound when lifting off the throttle that is heavily suppressed by the OEM airbox.
Constructed from T6061 aluminum and six-layer reinforced silicone, and paired with a powder-coated aluminum heat shield, the ARM G20 B58 Intake is engineered to provide high-flow performance, durability, and a quality fit and finish that complements the rest of the G-Series engine bay.
What's Included
- 1x ARM B58 Air Filter
- 1x ARM B58 Heat Shield
- 1x ARM B58 Heat Shield Aluminum Cover
- 5x Heat Shield Cover Screws and Washers
- 1x Heat Shield Securing Nut
- 1x ARM B58 MAF Pipe
- 1x ARM B58 Silicone Coupler
- 3x ARM Clamps
Fitment
- 2021-2025 BMW G42 M240i — B58
- 2021-2025 BMW G42 M240i xDrive — B58
- 2019-2024 BMW G20 M340i — B58
- 2019-2024 BMW G20 M340i xDrive — B58
- 2020-2024 BMW G21 M340i xDrive — B58
- 2021-2025 BMW G22 M440i — B58
- 2021-2025 BMW G22 M440i xDrive — B58
- 2021-2025 BMW G23 M440i — B58
- 2021-2025 BMW G23 M440i xDrive — B58
- 2021-2025 BMW G26 M440i Gran Coupe — B58
- 2021-2025 BMW G26 M440i Gran Coupe xDrive — B58
ARM Motorsports Lifetime Warranty
Every ARM Motorsports product is backed by a lifetime warranty that is automatically issued at the time of purchase. The warranty protects against defects in craftsmanship or fitment and entitles the customer to a replacement unit when covered by the warranty.
