Performance Increase : 10-14hp, 10-11ft-lb
*Images show our optional carbon engine cover.
The GR86 Intake is a culmination of testing numerous configurations with over 125 dyno runs to arrive at an optimised design. We tested both stock and tuned cars to assess the impact of changing the intake for a less restrictive version. The NA 2.4L Boxer engine is sensitive to intake air temperatures so our initial priority was to ensure a fully sealed system. Dyno testing revealed a dip in power around 6000rpm on the stock ECU. This dip persists no matter what the intake configuration is – even with all possible restrictions removed, a higher flowing intake creates a strong engine resonance at this rpm causing a momentary dip below the stock curve. The stock airbox has a baffling effect at this rpm but then also restricts the power at the top end. By iterating our design through testing different intake lengths, single and dual duct openings and even adding baffles, we arrived at a version which minimises the resonance dip while gaining 14hp at the top end on the stock ECU. Once the ECU is tuned we can see large mid-range gains and an elimination of the dip in power below the stock curve.
The Eventuri Difference
The GR86 Eventuri system uses our Patented Carbon fiber Housing which provides an aerodynamically efficient airflow path from the filter to the engine. Not just another cone filter with a heat shield but a unique design which invokes the Venturi affect and maintains laminar flow conditions to reduce the drag on the engine.
The Eventuri GR86 intake system consists of a number of components engineered to perform a specific purpose and fabricated to the highest of standards. We use 100% pre-preg carbon fiber with no fibreglass which means we can achieve a smooth internal surface to maintain smoother airflow. Here are the details for each component and the design ethos behind them:
Each intake system consists of:
- Carbon Fiber Patented Venturi Filter Housing with integrated MAF section
- Bespoke High Flow Dry Cone Filter
- Carbon Fiber Dual Feed Inlet Duct
- Laser Cut Front Air Scoops
- Custom Made Hardware
- Laser Cut Stainless Steel Brackets
- CNC Machined MAF Boss and Bracket Mounts
FILTER HOUSING ASSEMBLY
The filter housing comprises of our bespoke generation 2 filter, aluminium inlet cowl and the integrated MAF section. The carbon pod shrouds the reverse mounted filter and smoothly shapes the airflow down to the MAF section which then connects to the rear inlet tube. This changes the flow path from the OEM airbox where airflow enters the front of the airbox, changes direction by 90 degrees to travel through the panel filter and then changes direction again by 90 degrees to move through the MAF section. Our system is a lot more direct with airflow entering the front of the filter housing and and moving into the MAF section without any abrupt direction changes. The result is a smoother path from the filter to the turbo inlet tube and therefore the turbo is able to function with less drag. To ensure a reliable seal with the MAF sensor, we use a CNC machined mount secured to the carbon housing.
PATENTED TECHNOLOGY
Our patented filter housing has a smooth reduction in cross sectional area as it shrouds the filter and tapers down to the tubing. This geometry 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 patented design and a regular intake system. Our bespoke filters aid the airflow moving through the housings and allow for an even velocity profile as the airflow exits the housings. Further details can be read in the Technology and Filters pages.
CARBON DUCT
The duct feeds the filter housing with ambient airflow from the front bumper/grill section. Through testing several iterations we found that a dual intake where cold air was taken from both openings in the slam panel area, functioned in the least restrictive manner. The region in the front bumper area is saturated with cold air from our scoops and also from the natural design of the OEM cavity behind the bumper. The duct has an expanding rubber seal which mates to the filter housing to ensure heated engine bay air is kept away from the intake feed, but still allows for engine movement. It is mounted in 3 positions to ensure a secure fit.
FRONT SCOOPS
The final components are 2 front scoops which sit behind the lower grill to direct ambient air upwards into the opening of the duct. This aids in keeping IATs low while the car is in motion. For owners with aftermarket oil coolers who cannot use the scoops, the IATs will still remain minimal due to the natural saturation of cold air behind the bumper.
