Performance Plenum
Kit Includes
- Air Induction Kit
- Plenum by IPD
- Throttle Body 74mm
- Milltek Exhaust Cat back
Fits:
Porsche Boxster 987
Porsche Cayman 987C
Exhaust Muffler / Silencer Rear box (Catalysts Bypass System).
Sports deep sound muffler/exhaust offers a sportive sound and better throttle response. With secondary cat bypass to increased BHP. Milltek system is complete twin adjaustable stainless steel tails. Made from T304 stainless steel.
For the ultimate performance gains we recommend this set is fitted with an ECU remap giving BHP and Torque that you can really feel and superb sports car sound.
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Cayman 2.7L 987C 2006-08
Kit Includes
- Air Induction Kit
- Plenum by IPD
- Throttle Body 82mm
- DesignTek Exhaust Cat back
Exhaust Muffler / Silencer Sports Complete with Twin Stainless Steel Tail Pipes
DesignTek sports deep sound muffler/exhaust offers a sportive sound and better throttle response. With secondary cat bypass to increased BHP. Complete twin adjaustable stainless steel tails. Made from T304 stainless steel.
For the ultimate performance gains we recommend this set is fitted with an ECU remap giving BHP and Torque that you can really feel and superb sports car sound.
Fits:
Porsche Boxster 987
Porsche Cayman 987C
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Cayman 2.7L 987C 2006-08
Some early models up to 2006 have a 68mm throttle body so you might need to buy a 74mm throttle body part code 99760511502

Fits:
Porsche 987 GEN1 Cayman S 3.4L
Porsche 987 GEN1 Boxster S 3.4L
Porsche 987 GEN1 Cayman 2.7L
Porsche 987 GEN1 Boxster 2.7L
Download the detailed installation instructions.
The perfectly balanced mid engine Cayman/Boxster is Germany's canyon carving track meister. Unfortunately, the Cayman/Boxster was delivered slightly under powered from the factory so as not to threaten the Carrera's thrown. The Cayman/Boxster IPD intake plenum delivers increased performance that puts the Cayman/Boxster in the ring with the Carrera.
The IPD Plenum out performs every other intake system on the market. Don't be fooled by other competitors claiming to offer Plenums. All factory Porsche air distributors are of the "T" variety and therefore suffer from less than ideal air flow and intake air speed.
The genius and power behind the IPD plenums comes from the patented "Y" style design and optimized diversion areas to deliver real and impressive power that will transform your Cayman's/Boxster's performance and heighten your Porsche driving experience.
The Cayman/Boxster IPD Intake Plenums are available in 3 versions, each one specifically designed to meet the performance requirements of varying Cayman/Boxster enthusiasts. IPD offers the ultimate Cayman/Boxster performance upgrades, all the way from mild to wild.
The 74mm Cayman/Boxster S Plenum utilizes the factory 74mm throttle body. This version provides impressive power gains throughout the entire power band, especially in the midrange where it's most critical and most enjoyed.
The 74mm Cayman/Boxster S Plenum application is recommended for Cayman/Boxster S enthusiasts looking for considerable performance gains without pushing the performance envelope. Max horsepower is 14 and max torque is 12 which all comes in around 5600 RPM. Power gains are realized throughout the entire power band without any loses in power.
The IPD Cayman/Boxster S Plenum will provides the most impressive power gains of any engine upgrade available and will truly transform your Cayman/Boxster driving experience. The 74mm IPD Plenum is the best Cayman/Boxster modification on the market and will further compliment other mods such as exhaust, software and beyond.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
87174-2.7
The product you are viewing cross references to these numbers
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Boxster 987 S 3.2/3.4L 2005-08/08
- Porsche Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08

In fuel injected engines, the throttle body is the part of the air intake system that controls the amount of air flowing into the engine, in response to driver accelerator pedal input in the main. The throttle body is usually located between the air filter box and the intake manifold, and it is usually attached to, or near, the mass airflow sensor.
The largest piece inside the throttle body is the throttle plate, which is a butterfly valve that regulates the airflow. Have a larger diameter throttle body produces more air flow with equals more power. The upgrades should be used in conjunction with the competition plenums.
This is a 74mm Throttle body.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99760511502
The product you are viewing cross references to these numbers
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster 986 2.7L 2003-04
- Porsche Boxster S 986 3.2L 2003-04
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Boxster 987 S 3.2/3.4L 2005-08/08
- Porsche 996 TURBO 2000-05
- Porsche 996 GT2 2001-05
- Porsche Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
- Porsche Cayman 2.9L 987C MKII 2009-12
- Porsche Cayman S / R 3.4L 987C MKII 2009-12

In fuel injected engines, the throttle body is the part of the air intake system that controls the amount of air flowing into the engine, in response to driver accelerator pedal input in the main. The throttle body is usually located between the air filter box and the intake manifold, and it is usually attached to, or near, the mass airflow sensor.
The largest piece inside the throttle body is the throttle plate, which is a butterfly valve that regulates the airflow. Have a larger diameter throttle body produces more air flow with equals more power. The upgrades should be used in conjunction with the competition plenums.
This is a 74mm Throttle body.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99760511502
The product you are viewing cross references to these numbers
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster 986 2.7L 2003-04
- Porsche Boxster S 986 3.2L 2003-04
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Boxster 987 S 3.2/3.4L 2005-08/08
- Porsche 996 TURBO 2000-05
- Porsche 996 GT2 2001-05
- Porsche Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
- Porsche Cayman 2.9L 987C MKII 2009-12
- Porsche Cayman S / R 3.4L 987C MKII 2009-12
Performance Plenums – Maximise Airflow, Power & Efficiency for Your Porsche
A performance plenum is a critical upgrade for Porsche enthusiasts looking to improve throttle response, airflow efficiency, and overall engine performance. Sitting between the throttle body and intake runners, the plenum distributes incoming air evenly across all cylinders — ensuring consistent combustion and optimised power delivery.
At Design911, we offer a premium range of performance-engineered plenums designed specifically for Porsche models. Constructed from lightweight aluminium, carbon fibre, or composite materials, these units feature advanced internal flow geometry to reduce turbulence and increase air velocity.
Whether you’re enhancing a classic 911 or tuning a modern Cayman, our high-quality plenums are developed to deliver proven performance gains, sharper throttle response, and a more linear torque curve — perfect for both road and track use.
What Do Performance Plenums Do?
The plenum serves as an air distribution chamber that balances airflow between the cylinders. Upgrading to a performance plenum improves air charge efficiency, resulting in smoother engine breathing and increased power output.
Core Functions:
- Distribute
intake air evenly to all engine cylinders.
- Optimise
airflow dynamics for faster throttle response.
- Increase
air velocity and reduce pressure loss.
- Improve torque and mid-range performance.
- Enhance engine efficiency and fuel-air mixture stability.
A well-designed plenum ensures that every cylinder receives the right amount of air at the right time — unlocking smoother acceleration and more consistent power.
Why Do Plenums Fail or Require Replacement?
Over time, standard plenums can suffer from material fatigue, cracks, or restricted internal passages, all of which impact performance and reliability.
Common Causes of Failure Include:
- Cracks
or leaks from heat cycling and vibration.
- Carbon
build-up restricting airflow.
- Worn
gaskets or seals causing pressure loss.
- Plastic
deformation under extreme boost or temperature.
- Reduced efficiency due to outdated or restrictive design.
Signs of a failing plenum include loss of throttle response, poor fuel economy, uneven idle, or reduced torque. Replacing it with a performance-engineered unit restores full airflow efficiency and reliability.
Why Upgrade to a
Precision-Engineered Performance Plenum?
Upgrading your Porsche’s intake system with a high-performance
plenum enhances power delivery, throttle sharpness, and efficiency —
particularly when combined with a performance air intake and tuning.
Key Benefits:
- Increases horsepower and torque throughout the rev range.
- Delivers faster throttle response and improved drivability.
- Constructed from lightweight, heat-resistant materials.
- Improves airflow balance and reduces pressure drop.
- Direct-fit
compatibility for Porsche 911, Cayman, Boxster, and more.
- Ideal for performance tuning, track driving, and high-output builds.
Replacing restrictive intake components with a performance plenum unlocks your Porsche’s full potential, ensuring stronger mid-range power and greater engine efficiency.
Highlights:
- Performance-engineered plenums for Porsche tuning and upgrades.
- Improves airflow distribution, power delivery, and throttle response.
- Built from aluminium or carbon fibre for strength and weight reduction.
- Direct-fit installation with precision-sealed fittings.
- Perfect for high-performance, racing, or spirited road driving.
- Enhances engine sound and overall responsiveness.