Performance Increase with OEM ECU tune: 20-22hp, 8-13ft-lb

Introducing a groundbreaking achievement – the Eventuri Hybrid Airbox System, an innovative intake design for the legendary BMW E46 M3. This system combines the aggressive, motorsport-inspired tone of the CSL Airbox with the refined driveability and direct-fit convenience of a conventional intake. Previously, E46 M3 enthusiasts seeking the CSL airbox tone were forced to operate the engine without its MAF sensor, frequently resulting in costly ECU modifications or custom tuning, which compromised throttle response and overall driveability. Our Hybrid Airbox eliminates this trade-off, providing both the sound and performance of a CSL airbox without requiring a tune, while maintaining the driveability and consistent power delivery of a standard intake.

Part Numbers:

• EVE-E46ABX-CF-INT: BMW E46 M3 Hybrid Carbon Airbox with Full Carbon Intake
• EVE-E46ABX-CF-PLM: BMW E46 M3 Hybrid Carbon Airbox without Intake for existing Eventuri Intake owners

The Eventuri E46 M3 Hybrid Airbox System is available in 2 configurations, with and without the Eventuri intake. We offer the airbox without the intake to enable current E46 M3 owners with Eventuri intakes to reuse their existing filter housing and scoop. The Hybrid Airbox system features multiple components designed to fulfill specific functions and manufactured to exceptional standards. Here are the specifications for each component and the engineering philosophy behind them:

The complete Hybrid Airbox with intake configuration includes:

• Carbon Fiber Main Airbox
• Carbon Fiber Airbox Snorkel with MAF tube
• Thermoplastic Molded Trumpets with Stainless Steel Reinforcement Rings
• Carbon Fiber Filter Housing
• Bespoke Dry High Flow Filter
• Carbon Fiber Cold Air Scoop
• Stainless Steel Brackets and Flanges
• CNC Machined Breather Adapters
• Custom EPDM Flexible Coupler
• Silicon Couplers
• Crankcase Breather Hose
• Additional Vacuum Tubing

The primary airbox section contains the 6 trumpets along with the breather system connections. Constructed from prepreg carbon fiber, the airbox has been engineered to resonate during operation and deliver the distinctive CSL sound. A critical aspect of the construction involved ensuring long-term durability of the connection between the trumpets and the airbox. This was achieved through mechanical fasteners and gaskets to guarantee an airtight seal unaffected by thermal cycling and vibrations. An identical approach was implemented for the breather adapters.

The trumpets are manufactured using glass fiber reinforced thermoplastic. The injection molding technique provides precision while maintaining smooth internal surfaces for optimal airflow. This proved more beneficial than carbon fiber construction for each trumpet, as we can guarantee consistent form for every trumpet with precision unachievable through carbon. We also incorporated CNC machined stainless steel rings on the trumpets to prevent deformation when silicon couplers are secured onto them.

The snorkel or airbox cover efficiently directs airflow from the intake to the trumpet section. This component also integrates the MAF tube section where the OEM sensor attaches to a CNC machined MAF boss. The snorkel fastens to the primary airbox section using specially designed screws that engage plastic securing clips, preventing loosening under vibration.

CFD OPTIMISED The complete airbox geometry was refined through multiple iterations using CFD simulations to guarantee the trumpets received sufficient flow without experiencing restriction from geometric limitations or turbulence.

The filter housing consists of our custom generation 2 filter, stainless steel bracket and the carbon fiber housing. The carbon pod encases the reverse mounted filter and streamlines the airflow toward the plenum. This represents a critical element of the intake engineering where we have eliminated the complex flow path of the OEM airbox and consequently minimized the pressure loss throughout the entire system. This also guarantees that the airflow remains smooth when entering the MAF tube section of the airbox to enable the sensor to function without errors.

Our patented filter housings feature a gradual reduction in cross sectional area as they enclose the filters and narrow down to the tubing. This design creates the Venturi effect where the airflow gains velocity while preserving laminar conditions. It functions as a large velocity stack – below is a diagram illustrating the comparison between our patented design and a conventional intake system. Our custom filters support the airflow traveling through the housings and provide an even velocity profile as the airflow leaves the housings. Additional information can be found in the Technology and Filters pages.

100% Prepreg carbon fibre with a CNC machined collar – the air scoop channels ambient air directly into the filter opening. This scoop easily installs into the front right hand brake duct and efficiently fills the intake mouth with cold air. It has been engineered to occupy half the height of the duct to permit airflow to continue through the duct for the brakes. The scoop performs so effectively that even following spirited driving, the aluminium cowl at the intake mouth will remain cold to touch.