The new 981 Boxster and Cayman Plenums will finally be available this month (October 2013). After a very extensive R & D program we are proud to launch the new 981 IPD 82mm Competition Plenums. We will only be offering "Competition" versions of the 981 Plenums which replaces the factory 74mm throttle body with the larger 997 GT3 82mm throttle body. This combination has proven to be considerably more popular and deliver even more performance.
The 981 intake is nearly identical to the 987.2 intake. Porsche made a few upgrades with the 981, most notably being that the 981 draws outside air from both driver and passenger air intakes instead of the driver's side only as previously found with all 986, 987 and 987.2 applications. IPD has developed a custom silicone hose designed to perfectly fit the larger 82mm TB and considerably improve air flow.
The new 981 Plenums also benefits from the internal dimpling effect that we are now implementing on all future Plenums. This internal dimpling allows us to control the boundary layer and maximize air flow. Just like a dimpled golf ball travels farther than a smooth golf ball. Controlled turbulent air creates less friction and "tumbles" over a given area more efficiently. We have been experimenting with dimpling the insides of the Plenums for the past 2 years and have seen quantifiable performance improvements with both Turbo and NA applications.
Power gains with the 981 Competition Plenum are 13 horsepower and 12 foot pounds of torque at the wheels. The bulk of the power gains from the IPD Plenum begin around 4000 rpm, continues all the way through to redline and become fully realized in the 6000 rpm range. IPD performance gains stay above both factory power curves throughout the entire rev range. Initial throttle response is significantly improved with a very noticeable and stronger launch when the driver jumps on the throttle at any rpm or speed.