Eventuri Audi S4 S5 B9 Intake System

Eventuri Audi S4 / S5 B9 Intake System is a high-performance carbon fiber intake system developed specifically for the Audi B9 S4 and S5, with a focus on providing less restrictive airflow to the turbocharger while maintaining low intake temperatures.

The B9 S4/S5 engine bay can become heat soaked quickly, making a conventional open cone intake less effective in real-world conditions. Eventuri therefore developed a fully sealed intake system that manages both airflow and temperature rather than focusing solely on increasing filter size.

At the heart of the system is Eventuri's Patent Pending Carbon Fiber Venturi Housing, which incorporates the filter and intake tube into a single assembly. The reverse-mounted Generation 2 High-Flow Filter is enclosed by the carbon housing, which progressively shapes the airflow toward the turbo intake tube.

This smooth reduction in cross-sectional area creates a Venturi Effect, accelerating the airflow while helping maintain a more consistent and laminar flow profile. Eventuri also eliminates the convoluted factory rubber section between the intake and engine, replacing it with a solid integrated tube for a smoother transition into the turbocharger.

The system also features a dedicated Carbon Fiber Intake Duct that channels ambient air from the front scoop toward the filter housing. The duct creates a sealed volume of cool ambient air ahead of the filter, giving the filter a ready supply of outside air while helping isolate it from hot engine-bay air.

A flexible rubber seal around the duct maintains the separation between the intake and engine-bay heat while still allowing the carbon housing to move with the engine. Eventuri also incorporates a secondary opening at the rear of the duct, positioned within a cooler region of the engine bay, to further improve the available airflow.

At the front of the system, the Carbon Fiber Air Scoop is designed with a constant bend radius to efficiently direct incoming ambient air into the intake duct. This helps maintain low inlet temperatures and allows the system to recover from heat soak more quickly after the vehicle has been stationary.

Eventuri's road testing demonstrated a measurable improvement with the intake alone. Using a V-Box, 60–130 mph acceleration improved from 14.72 seconds with the stock intake to 14.24 seconds with the Eventuri system, a reduction of almost 0.5 seconds. The 100–200 km/h time also improved from 12.45 seconds to 12.12 seconds.

Eventuri reports a 13–17 hp and 15–20 ft-lb performance gain for the system, while noting that real-world gains can be influenced by airflow conditions. The combination of the sealed intake architecture, Venturi housing and cold-air supply allows the system to deliver its benefits beyond what a simple dyno comparison may suggest.

The complete system combines a Carbon Fiber Venturi Housing with Integrated Tube, Generation 2 High-Flow Filter, Carbon Fiber Intake Duct, Carbon Fiber Front Scoop, Silicon Couplers, OEM-Spec Hose Clamps, Laser-Cut Stainless Steel Brackets and CNC-Machined Mounting Stubs.