The 991 Turbo Eventuri intake system was developed through extensive real-world testing with the goal of allowing turbos to operate more efficiently. By replacing the stock airbox with patented individual Venturi filter housings, the turbos are able to spin and generate boost with less resistance. As a result, wastegate duty cycles are reduced, resulting in peak boost at low rpm and therefore increased performance. The two individual filters provide a larger filtration area than the single stock panel filter. Additionally, to keep inlet air temperatures low, the Venturi housings are sealed against an air duct that draws ambient air from the same location as the stock system. Because the 911 Turbo engine bay is so densely packed, high IATs can only be avoided by ensuring a completely sealed intake system. The combination of a smoother airflow path to each turbo with low IATs results in higher performance and sharper throttle response compared to the stock airbox.
The intake was road tested using a Vbox unit to record acceleration from 60-130 mph. Tests were performed on the same stretch of road, on the same day every time to minimize variables. The results show that with just the added intake, on stock software, acceleration times from 60-130 mph were reduced by 0.2 seconds, which is a significant improvement at those speeds.
Acceleration results summary:
- 60-130 mph with stock intake = 8.04 seconds
- 60-130 mph with Eventuri intake = 7.83 seconds
The advantages are due to a combination of reasons:
1) Individual venturi housings separate the flow path for each turbo, allowing them to operate more efficiently.
2) Venturi housings ensure a smooth transition from the filter to the intake tubes, maintaining laminar airflow.
3) Intake air temperatures are kept to a minimum by ensuring a sealed system to avoid drawing hot air into the engine bay.
The Eventuri 991 Turbo intake system is made up of a series of components designed to perform a specific purpose and manufactured to the highest standards. Here are the details for each component and the design ethic behind them:
Each intake system consists of:
- 2 x Carbon Fiber Venturi Housings with Integrated Tubes
- 2 x Generation 2 High Flow Filters on size
- 2 x Aluminium Intake Hoods
- Carbon Fibre Inlet Duct
- Laser Cut Stainless Steel Bracket
INTAKE HOUSING ASSEMBLY INTAKE
The filter housings comprise our custom-fit second-generation filters, aluminum intake cowls, carbon pods and integrated pipes. The carbon pods wrap around the reverse-mounted filters and smoothly shape the airflow to the stock turbo inlet pipes. By separating the inlet path and having a dedicated filter for each turbo, the intake allows the turbos to run more efficiently. Crucially, the venturi housings extend organically in a gentle curve from the filter opening to the stock turbo pipe. This ensures that airflow remains as smooth as possible throughout the system. Smooth airflow means less resistance, so the turbos can reach maximum boost earlier in the rpm range. This also means that throttle response is sharper.
PATENTED TECHNOLOGY
Our patented filter housings feature a smooth reduction in cross-sectional area as they wrap around the filters and taper down to the tube. This geometry is reminiscent of the Venturi effect where the airflow accelerates while maintaining laminar conditions. It can be thought of as a large velocity stack - below is a diagram showing how our patented design compares to a typical intake system. Our custom-designed filters help the airflow move through the housings and allow for a smooth velocity profile as the airflow exits the housings. Further details can be read on the Technology and Filters pages.
INTAKE DUCT
The intake duct seals against the underside of the trunk lid using the stock rubber cushion and then extends down to seal against the filter housings. Constructed from 100% pre-preg carbon fiber, the intake duct ensures that the intake only draws ambient air and not heated air from the engine bay. Again, to maximize flow efficiency, the transition from the circular openings for the filter housings to the single air entry point is as seamless as possible. The duct also features 2 exhaust pipes that direct water away from the filters. The pipes are designed so that the air intakes draw a minimal amount of air from inside the engine bay due to the greater flow resistance in the pipes compared to the opening at the top of the duct. The complex geometry of the duct was necessary to free up the various components in the 991 Turbo's engine bay.
STIRRUP WORK
The brackets are laser cut from stainless steel and powder coated. We went to great lengths to ensure the intakes have a precision fit using the stock airbox mounting locations. The brackets not only reinforce the intakes to the frame, but also allow the engine components to be bolted on as is with the stock airbox. To save weight, each bracket has specially shaped cutouts that remove material but allow the overall structure to remain rigid. The complete system comes together to provide an audible and noticeable performance improvement over the stock airbox system.
