The sensational mid-engine Porsche GT4 has received unanimous praise from Porsche enthusiasts around the globe. It received even more positivity after installing the IPD Plenum and larger 82mm GT3 throttle body that the engine was designed for in the 991 Carrera S. However, as is the usual case, they had to handicap the car’s grade track machine by squeezing the inlet track with a smaller 74mm throttle body, resulting in limited engine potential.
The IPD Plenum dramatically improves power and torque gains throughout the entire RPM band, while also delivering a smoother and more linear power curve. This GT4 dyno test session shows net gains from launch to redline with the greatest gains (18 WHP / 17 Torque) being realized at 5200 and 6900 RPM.
Note from IPD: After a very extensive R&D program we are proud to launch the new 981 IPD 82mm Competition Plenums. We only offer “competition” versions of the 981 Plenums which upgrades 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. This Competition version will work with both 3.4L “S” and 2.9L “non-S” applications.
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.
Power gains with the 981 Competition Plenum are virtually the same as with the 987.2 Competition Plenum, putting down 20 horsepower and 16 foot pounds of torque at the wheels. The bulk of the power gains from the IPD Plenum begin around 4,000 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.
981 DFI Cayman/S/GTS/Spyder/GT4 (3.4L) IPD “Competition” Plenum (Part #81482-3.4)