BMW G29 Z4 B58 Eventuri Intake System
Performance gains: 17-20 hp, 11-20 ft-lb
Suitable for: BMW G29 Z4 M40i
The Eventuri air intake for the BMW G29 Z4 M40i is designed to provide the turbo with less restrictive airflow while keeping intake temperatures low. When developing this air intake, heat and volume are the most important considerations for turbocharged engines. The Z4's air intake system is located next to the exhaust manifold, which ensures that the engine bay warms up quickly. High temperatures are detrimental to engine performance, as the turbo must build boost using heated, less dense air. The only way to keep intake air temperatures (IAT) to a minimum is with a completely sealed air intake.
In the standard configuration, however, there is only one air intake taking in air, which is a limitation. During development, we discovered an additional opening in the wheel arch area, which we exploited by adding a second air intake to our air box. Additionally, our sealed air box has a heat shield with a gold reflective layer that minimizes radiative heat transfer from the exhaust manifold. To maximize volume, we made the air box as large as possible, with space for strut braces to be added if necessary. The standard serpentine intake tube has been replaced with a smooth carbon fiber tube, which also has a larger internal volume with a starting diameter of 111mm (4.4″) that gradually tapers towards the turbo inlet, ensuring the smoothest possible airflow from the filter to the turbo inlet. Finally, we use a custom high-flow dry filter that is ISO tested for filtration performance and has a larger filtration surface area than the standard filter.
What makes this Eventuri intake system special? The Eventuri Z4 B58 intake system consists of several components that have been specially developed and manufactured to the highest standards. We use 100% pre-preg carbon fiber without any fiberglass, which allows us to achieve a smooth internal surface and maintain a smooth airflow. Here are the details of each component and the design idea behind it:
Every intake system consists of:
- Carbon fiber air box with dual air intakes
- Custom High Flow Dry Cone Filter
- Carbon fiber intake pipe with a 111mm opening
- CNC machined temperature sensor mount
- CNC machined breath adapter
- Heat protector with gold reflective layer
- Laser cut stainless steel brackets
- Silicone coupling with OEM-specified clamps
Dual Feed Carbon Fiber Airbox
Made from Prepreg Carbon Fiber, the air box has two functions: to cover the filter from engine compartment heat and to provide two cold air intakes. Since the air box is positioned next to the exhaust manifold, it is essential that the filter is completely sealed to prevent heated air from entering the air box. To achieve this, we designed a laser cut plate with a rubber sealing strip that covers the air intake. The air intake tube passes through the plate and the rubber seal prevents hot air from entering the air box. The air box also has a heat shield with a gold reflective layer on the side of the exhaust manifold, which minimizes radiative heat transfer.
However, with a fully sealed airbox there is a restriction on the cold air intake. The standard airbox draws air through a single duct that leads to the front bumper. During development we discovered another space between the wheel arch and the chassis where the airbox sits, and we exploited this space by extending a second air intake at the rear of our design, which protrudes into the wheel arch. This allows the turbo to draw air from a larger area, reducing the restriction. Additionally, we added an internal splash guard to deflect water away from the filter.
Carbon Inlet Pipe
The stock intake tube features a flexible, serpentine section that accommodates engine movement, but this can disrupt the airflow by creating multiple angles and surfaces that cause turbulence. We replace this with our carbon fiber tube which is smooth and has a larger internal volume. Unlike most aftermarket intakes, we’ve optimized the intake tube design by increasing the diameter of the tube. The OEM tube has an internal diameter of 80.8mm (3.2″) on the filter side, while our tube has an internal diameter of 109mm (4.3″). This creates a significant 82% increase in cross-sectional area over the stock tube. The tube gradually tapers towards the turbo inlet to keep the airflow as laminate as possible.
Bespoke Cone Filter
Our cone filter is made of non-woven mesh material, double layered, and is ISO tested to ensure filtration meets OEM standards. The filter is cleanable and highly stable at high temperatures, with the base material being urethane. The filter has an internal flow guide that helps to converge the airflow while reducing the possibility of a stagnation point in the center of the filter surface. The filter media has a significantly larger surface area than the standard panel filter.
With this intake system, the BMW Z4 B58 receives a powerful performance upgrade, with improved airflow and lower intake temperatures, resulting in a significant increase in performance.