AUDI B8 RS5 / RS4
Performance Gain: 15-20hp, 12-18ft-lb (At The Wheels)
Some of the photos above show our optional carbon engine and slam panel covers found HERE
The Audi RS5/RS4 Eventuri intake was developed after consultation and support from RS5 enthusiasts. We have completely re-engineered the inlet track from the ducts to the filters and the inlet tubes. The restrictive stock airboxes and duct feeds have been replaced with a highly efficient ? fully sealed system with smooth transitions to allow the airflow to remain full and laminar. The resulting performance gains, sound and aesthetics are industry leading for this platform.
The Eventuri Difference
The RS5/RS4 Eventuri system uses our Patent Pending Carbon fibre Housings which provide an aerodynamically efficient airflow path from the filters to the throttle bodies. Not just another cone filter with a heat shield but a unique design which invokes the Venturi affect. You can read more about the housing design and how it works HERE
n order to realise the gains from the intake, the S5 needs a remap so that any extra boost pressure is not bled away by the ECU. The car we used had a smaller pulley and stage 2 remap upgrade and we tested it with the stock airbox first, then with the Eventuri intake. The only change between runs was the intake system. Both tests had the remap and pulley upgrade.
Dyno was carried out on a Dyno Dynamics system with the bonnet closed for both stock and Eventuri systems. This is important because leaving the bonnet open does not represent road conditions.
As can be seen, in the low to mid RPM range there is a healthy gain in torque between 25ft-lb and 34ft-lb. This gain is instantly noticeable on the road with the car pulling away more aggressively and having better throttle response. In the higher RPM range where power takes over from torque, there is a decent gain of 19hp to 22hp with a peak RPM gain of approximately 17hp.
The gains are from a combination of reasons:
1) The sealed system keeps IATs low – especially with the front air scoop which forces air into the system.
2) The Venturi housing provides a smooth transition from the filter to the intake tube which maintains laminar flow. This helps the charger to run more efficiently.
3) The entire system is constructed from pure pre-preg carbon fibre which is great at insulating from heat.
The Eventuri B8, B8.5 S4/S5 intake system consists of a number of components engineered to perform a specific purpose and fabricated to the highest of standards. Here are the details for each component and the design ethos behind them:
Each intake system consists of:
- Carbon Fibre Venturi housing
- High Flow Double Cone Air Filter
- Aluminium Cowls for smooth airflow entry
- Carbon Fibre Inlet Tubes with smooth taper
- Carbon Fibre Intake Duct with secondary inlet and flexible tubing
- Carbon Fibre Front Scoop
- Laser Cut Stainless Steel Scoop Extension Plate
- High Quality Silicon Couplers and OEM Spec Hose Clamps
- Breather filter with adapter and laser cut bracket
Carbon Intake Housing Assembly
The filter housing comprises of a high flow filter, aluminium cowl, laser cut bracket and the carbon pods itself. The carbon pods shroud the reverse mounted filter and smoothly shape the airflow down to the intake tubes. This smooth reduction in cross sectional area invokes the Venturi effect where the airflow accelerates whilst maintaining laminar conditions. It can be thought of as a large velocity stack – below is a diagram to show the comparison between our patent pending design and a regular intake system. Further details can be read in the Technology page.
Carbon Fibre Intake Duct
The duct channels ambient air from the scoop to the filter housing. It fits inside the OEM ducting system and smoothly transitions to the circular filter housing shape. In order to ensure a good seal against engine bay heat – the duct also has a flexible rubber edging around the openings which press against the filter housings creating the desired seal yet allowing the housings to move with the engine. To further enhance the airflow we added a secondary inlet at the base of the duct to which a flexible tube is attached. this tube is then positioned under the headlamp where it can draw ambient air. These geometrically complex pieces are a key part of our S4/S5 design.
To illustrate – here is a CAD animation showing the duct:
Carbon Fibre Intake Tubes
Our intake tubes are again crafted from 100% prepreg carbon fibre. Each tube has an integrated vacuum/boost line insert which is CNC machined from aluminium. The tubes smoothly carry the airflow to the throttle bodies by ensuring there are no sharp or sudden bends. The smooth bend geometry ensure laminar flow is maintained from the filters to the exits.
Carbon Fibre Air Scoop
The final carbon components in this system is the front scoop – essential to direct ambient air to the ducts and then to the filters.
The scoops were designed with a constant bend radius for maximum efficiency in directing the incoming air to the duct openings. They allow the inlet air temperatures to be as low as possible and increase the rate of drop in IATs after the system is heat soaked during a standstill.
All the components come together in the engine bay to produce a genuine improvement in the driving experience as well as providing an incredible visual display of form and function in complete harmony.