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Electronic Fuel Injection Throttle Kits
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 964 (911) C2 1989-93
- Porsche 964 (911) C4 1989-93
- Porsche 964 (911) RS 3.6L 1991-93
- Porsche 964 (911) RS 3.8L 1991-93
Mechanical Throttle Linkage Assembly for Individual Throttle Body (ITB) Systems
The Rennen Mechanical Throttle Linkage Assembly is a precision-engineered solution designed specifically for Rennen Individual Throttle Body (ITB) conversions. Available in two configurations, one for the traditional solid accelerator rod system found in classic Porsche 911 models and another for the accelerator cable system used on Porsche 964 models, this assembly provides smooth, accurate and reliable throttle operation.
Fits:
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 964 (911) C2 1989-93
- Porsche 964 (911) C4 1989-93
- Porsche 964 (911) RS 3.6L 1991-93
- Porsche 964 (911) RS 3.8L 1991-93
As one of the most critical components in an ITB installation, the throttle linkage transfers driver input directly to the throttle bodies, ensuring precise synchronisation and immediate engine response. Designed to integrate seamlessly with Rennen by JSR ITB systems, the linkage assembly delivers the direct mechanical feel Porsche enthusiasts expect while maintaining excellent throttle control and drivability.
Whether you're building a high-performance road car, a track-focused machine or a fully restored air-cooled Porsche, a properly engineered throttle linkage is essential for unlocking the full potential of an ITB conversion.
What Does a Mechanical Throttle Linkage Do?
The throttle linkage connects the accelerator pedal mechanism to the individual throttle bodies, translating driver input into precise throttle movement.
Its primary functions include:
- Controlling throttle opening and closing
- Synchronising multiple throttle bodies
- Delivering accurate throttle response
- Providing smooth pedal feel
- Maintaining consistent throttle operation
- Supporting reliable engine performance
The assembly is available in two versions:
Porsche 911 Solid Accelerator Rod Version
Designed for classic Porsche 911 models that utilise the factory mechanical rod linkage system. This version integrates with the original accelerator rod arrangement while providing accurate control of the ITB system.
Porsche 964 Accelerator Cable Version
Designed for Porsche 964 models equipped with a throttle cable system. This version provides a clean and reliable connection between the accelerator cable and the individual throttle body assembly.
Why Is an ITB Upgrade So Appealing?
Individual Throttle Body systems are widely considered one of the most rewarding naturally aspirated performance upgrades available for Porsche engines.
Unlike conventional intake systems that use a shared plenum, ITBs provide each cylinder with its own dedicated throttle body, allowing the engine to breathe more efficiently and respond instantly to throttle inputs.
Benefits of a Rennen by JSR ITB conversion include:
- Immediate throttle response
- Improved airflow efficiency
- Enhanced engine breathing
- Increased performance potential
- Greater tuning flexibility
- Distinctive induction sound
- Improved driver engagement
- Motorsport-inspired driving characteristics
For many Porsche enthusiasts, the combination of razor-sharp throttle response and an unmistakable induction note makes ITBs one of the most desirable engine upgrades available.
Why a Quality Throttle Linkage Matters
Even the best throttle bodies cannot perform correctly without a precise and reliable linkage system.
A high-quality linkage assembly helps:
- Deliver accurate throttle control
- Maintain throttle body synchronisation
- Improve pedal feel
- Eliminate unwanted play or movement
- Support consistent engine tuning
- Improve overall drivability
- Maximise ITB performance benefits
A properly engineered linkage transforms the driving experience by creating a direct connection between the driver and the engine.
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 964 (911) C2 1989-93
- Porsche 964 (911) C4 1989-93
- Porsche 964 (911) RS 3.6L 1991-93
- Porsche 964 (911) RS 3.8L 1991-93
Rennen Throttle Position Sensor (TPS) for Rennen by JSR Individual Barrel Throttle Body Upgrades
The Rennen Throttle Position Sensor (TPS) is a critical engine management component designed specifically for use with Rennen by JSR Individual Barrel Throttle Body (ITB) upgrades. Mounted directly to the throttle assembly, the TPS continuously measures throttle opening angle and relays this information to the engine control unit (ECU), allowing precise fuel and ignition calculations throughout the engine's operating range.
Fits:
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 964 (911) C2 1989-93
- Porsche 964 (911) C4 1989-93
- Porsche 964 (911) RS 3.6L 1991-93
- Porsche 964 (911) RS 3.8L 1991-93
When upgrading a Porsche engine to Individual Barrel Throttle Bodies, accurate throttle position data becomes even more important. The instantaneous airflow characteristics of ITBs demand rapid ECU response, and the TPS provides the critical information required to deliver smooth drivability, sharp throttle response and maximum performance.
Whether you're building a fast road Porsche, a track day machine or a dedicated motorsport engine, the TPS is an essential component in achieving a professional and properly calibrated ITB installation.
What Does a Throttle Position Sensor Do?
The Throttle Position Sensor measures the exact position of the throttle barrels and communicates this information directly to the ECU.
The ECU uses this data to determine:
- Throttle opening percentage
- Driver demand
- Acceleration enrichment requirements
- Ignition timing adjustments
- Fuel delivery calculations
- Deceleration fuel cut strategies
- Idle and part-throttle control
A properly functioning TPS helps provide:
- Instant throttle response
- Accurate fuel mapping
- Smooth acceleration
- Stable idle quality
- Improved drivability
- Enhanced engine performance
- Reliable ECU operation
Without accurate throttle position data, modern engine management systems cannot react correctly to driver inputs.
Why Is a TPS Essential for ITB Conversions?
Individual Barrel Throttle Bodies dramatically improve airflow and engine response, but they also require more precise engine management control.
Unlike traditional airflow-restricted intake systems, ITBs allow airflow to increase almost instantly as the throttle opens. The ECU therefore relies heavily on TPS input to determine fuel and ignition requirements during rapid throttle movements.
The TPS allows:
- Accurate throttle-based load calculations
- Faster ECU response times
- Improved transient fueling
- Smoother acceleration
- Better throttle modulation
- Enhanced drivability
- More accurate engine calibration
Without a TPS, an ITB-equipped engine can suffer from hesitation, poor throttle transitions and inconsistent performance.
Why Are Barrel ITB Upgrades So Popular?
Rennen by JSR Barrel Throttle Bodies are engineered to maximise airflow while delivering a true motorsport-inspired driving experience.
Benefits include:
- Instant throttle response
- Increased airflow efficiency
- Improved engine breathing
- Enhanced power potential
- Greater tuning flexibility
- Exceptional induction sound
- Improved driver engagement
- Stunning engine bay appearance
When combined with a correctly calibrated ECU, MAP sensor and TPS, the result is an engine that delivers exceptional responsiveness and performance.
Why Choose the Rennen TPS?
Developed specifically for Rennen by JSR ITB applications, this sensor delivers the accuracy and reliability required for professional-level ECU calibration and performance tuning.
Benefits include:
- Accurate throttle position measurement
- Compatible with Rennen by JSR Barrel ITBs
- Supports standalone ECU systems
- Improves tuning precision
- Enhances throttle response
- Supports motorsport and fast road applications
- Reliable long-term performance
- Essential for modern EFI engine management
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
Rennen Crankshaft Position Sensor Wheel for Rennen by JSR Individual Barrel Throttle Body Upgrades
The Rennen Crankshaft Position Sensor Wheel is a precision-engineered trigger wheel designed specifically for use with Rennen by JSR Individual Barrel Throttle Body (ITB) conversions. Supplied as the toothed outer ring only, this component is designed to be TIG welded directly onto the engine's crankshaft pulley, creating the precise trigger pattern required by modern standalone engine management systems.
Fits:
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
When upgrading a Porsche engine to Rennen by JSR Barrel ITBs, accurate engine position data becomes essential. The trigger wheel works in conjunction with the crankshaft position sensor to provide the ECU with precise information regarding crankshaft position and engine speed. This data forms the foundation of all ignition and fuel injection calculations.
Without a trigger wheel and crankshaft position sensor system, modern programmable ECUs cannot accurately control ignition timing, fuel injection events or advanced engine management strategies. As a result, the trigger wheel is one of the most important supporting components required for a professional ITB conversion.
What Does a Crankshaft Position Sensor Wheel Do?
The crankshaft position sensor wheel rotates with the engine crankshaft and passes a series of precision-machined teeth past the crankshaft position sensor.
As the teeth pass the sensor, electrical signals are
generated and transmitted to the ECU. The ECU uses this information to
determine:
- Crankshaft position
- Engine speed (RPM)
- Ignition timing reference
- Fuel injection timing
- Engine synchronisation
- Rev limiting functions
- Sequential engine management strategies
This information allows the ECU to accurately control every aspect of engine operation.
Why Is a Trigger Wheel Required for ITB Conversions?
Rennen by JSR Barrel Throttle Bodies are typically installed alongside a standalone ECU to maximise performance and drivability.
The ECU requires an accurate crankshaft reference signal to:
- Fire ignition coils at the correct time
- Control fuel injection events
- Support sequential fuel injection systems
- Enable advanced ignition mapping
- Improve throttle response
- Stabilise idle quality
- Improve engine calibration accuracy
The trigger wheel effectively provides the ECU with a digital reference point for every engine revolution.
Without it, modern EFI systems cannot operate correctly.
TIG Welding Installation
This Rennen Trigger Wheel is supplied as the toothed outer ring only and is intended to be TIG welded directly onto the crankshaft pulley as part of the engine management conversion process.
Benefits of this design include:
- Precise positioning on the pulley
- Excellent durability
- Secure long-term attachment
- Motorsport-grade reliability
- Compatibility with custom engine management installations
- Professional conversion solution
Correct installation and positioning are critical to ensure accurate sensor readings and ECU synchronisation.
Why Are Barrel ITB Upgrades So Popular?
Rennen by JSR Barrel Throttle Bodies deliver one of the most dramatic upgrades available for naturally aspirated Porsche engines.
Benefits include:
- Instant throttle response
- Increased airflow efficiency
- Improved engine breathing
- Greater power potential
- Enhanced torque delivery
- Exceptional induction sound
- Motorsport-inspired driving experience
- Stunning engine bay presentation
When paired with modern engine management and accurate crankshaft position monitoring, the system delivers outstanding performance and drivability.
Why Choose the Rennen Crankshaft Position Sensor Wheel?
Developed specifically for Rennen by JSR ITB applications, this trigger wheel provides the precision required for professional ECU calibration and reliable engine operation.
Benefits include:
- Accurate crankshaft position reference
- Supports standalone ECU systems
- Essential for EFI conversions
- Enables precise ignition timing
- Supports advanced fuel injection strategies
- Suitable for road and motorsport applications
- Reliable long-term performance
- Professional-grade installation solution
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 964 (911) C2 1989-93
- Porsche 964 (911) C4 1989-93
- Porsche 964 (911) RS 3.6L 1991-93
- Porsche 964 (911) RS 3.8L 1991-93
Rennen Vacuum Fittings & Tube Set for Use with Rennen Vacuum Manifold
Complete your Porsche Barrel Individual Throttle Body conversion with the Rennen Vacuum Fittings & Tube Set, specifically engineered for use with the Rennen by JSR Vacuum Manifold. This installation kit provides the vacuum fittings, connectors and tubing required to correctly link each throttle body to the vacuum manifold, ensuring a stable and reliable vacuum signal for engine management and ancillary systems.
Fits:
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 964 (911) C2 1989-93
- Porsche 964 (911) C4 1989-93
- Porsche 964 (911) RS 3.6L 1991-93
- Porsche 964 (911) RS 3.8L 1991-93
Designed exclusively for Rennen by JSR Barrel ITB systems, this kit forms an essential part of the overall induction and engine management package. By combining the vacuum signals from each individual throttle body, the system creates a stable vacuum source that can be used for MAP sensors, fuel pressure regulators, idle control strategies and other engine management functions.
For any EFI-controlled Individual Throttle Body conversion, achieving a consistent vacuum signal is critical to drivability, tuning accuracy and overall engine performance.
What Does the Vacuum Fittings & Tube Set Do?
Individual throttle body systems generate vacuum independently from each intake runner. Because these vacuum signals fluctuate rapidly, they need to be combined through a vacuum manifold system to create a smooth and usable signal.
The Rennen Vacuum Fittings & Tube Set allows:
- Connection of each throttle body to the vacuum manifold
- Stable vacuum signal generation
- Accurate MAP sensor readings
- Improved ECU tuning capability
- Consistent engine load measurement
- Reliable idle control strategies
- Enhanced drivability
Without the correct vacuum plumbing, modern engine management systems can struggle to interpret engine load accurately.
Why Is a Vacuum Manifold Important on Barrel ITBs?
Barrel throttle bodies provide exceptional airflow and throttle response but naturally produce highly pulsed vacuum signals.
The Rennen by JSR Vacuum Manifold and associated fittings
help:
- Smooth vacuum fluctuations
- Improve MAP sensor accuracy
- Enhance fuel delivery calculations
- Improve ignition mapping accuracy
- Stabilise idle operation
- Improve low-speed drivability
- Simplify ECU calibration
The result is a more refined and predictable engine that retains all the performance benefits of an Individual Throttle Body conversion.
Why Are Individual Throttle Body Upgrades So Popular?
Individual Throttle Body systems are widely regarded as one of the most desirable naturally aspirated performance upgrades available for Porsche engines.
Benefits include:
- Instant throttle response
- Improved airflow efficiency
- Enhanced engine breathing
- Increased performance potential
- Greater tuning flexibility
- Motorsport-inspired induction sound
- Improved driver engagement
- Stunning engine bay appearance
When combined with modern EFI systems and correctly configured vacuum management, ITBs deliver exceptional performance and drivability.
Why Choose the Rennen Vacuum Fittings & Tube Set?
This kit has been developed specifically to work with the Rennen by JSR Vacuum Manifold and Barrel ITB systems.
Benefits include:
- Correct fitment for Rennen systems
- Simplified installation
- Reliable vacuum connections
- Improved tuning accuracy
- Stable engine management signals
- Professional conversion finish
- Suitable for road and motorsport use
- Supports advanced ECU functionality
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 964 (911) C2 1989-93
- Porsche 964 (911) C4 1989-93
- Porsche 964 (911) RS 3.6L 1991-93
- Porsche 964 (911) RS 3.8L 1991-93
Rennen Vacuum Manifold for Individual Throttle Body (ITB) Systems
The Rennen Vacuum Manifold is a key component of the Rennen
Individual Throttle Body (ITB) Upgrade system, designed to provide a stable and
consistent vacuum signal from multiple throttle bodies on high-performance
Porsche engines. Engineered specifically for use with Rennen ITB installations,
this vacuum manifold simplifies vacuum management while supporting modern
engine management systems, fuel pressure regulators, brake servo systems and
manifold pressure sensors.
Fits:
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 964 (911) C2 1989-93
- Porsche 964 (911) C4 1989-93
- Porsche 964 (911) RS 3.6L 1991-93
- Porsche 964 (911) RS 3.8L 1991-93
Individual Throttle Body systems dramatically improve airflow and throttle response by providing each cylinder with its own dedicated throttle plate. However, because each throttle body only generates a small and highly fluctuating vacuum signal, a vacuum manifold is required to collect and balance vacuum from all cylinders into a stable source that can be used by engine management and ancillary systems.
For Porsche enthusiasts seeking improved engine response, sharper acceleration and enhanced induction sound, the Rennen ITB system delivers one of the most desirable upgrades available for naturally aspirated Porsche engines.
What Does a Vacuum Manifold Do?
A vacuum manifold combines vacuum signals from each individual throttle body into a single, stable vacuum source.
This allows critical engine systems to operate correctly,
including:
- Engine management systems
- MAP (Manifold Absolute Pressure) sensors
- Fuel pressure regulators
- Brake servo assistance systems
- Idle control systems
- Vacuum-operated accessories
By smoothing the pulsing vacuum signals generated by individual throttle bodies, the manifold improves tuning accuracy and system reliability.
Why Is an ITB Upgrade So Appealing?
Individual Throttle Body systems are widely regarded as one of the most effective naturally aspirated performance upgrades available for Porsche engines.
Unlike a conventional plenum intake system, each cylinder receives air through its own dedicated throttle body, resulting in significantly improved airflow characteristics and immediate throttle response.
Benefits of a Rennen ITB upgrade include:
- Sharper throttle response
- Improved engine breathing
- Increased airflow efficiency
- Enhanced induction sound
- Greater driver engagement
- Improved tuning flexibility
- Increased performance potential
- Motorsport-inspired engine character
For many Porsche enthusiasts, the instant throttle response and distinctive intake sound are among the most rewarding aspects of an ITB conversion.
Why Replacement or Installation Matters
A properly designed vacuum manifold is essential for extracting the full benefits of an ITB conversion.
Without a stable vacuum source, engine management systems may receive inconsistent readings, affecting drivability, idle quality and tuning accuracy.
Benefits include:
- Stable vacuum signal generation
- Improved ECU calibration accuracy
- Better idle characteristics
- Consistent fuel pressure regulation
- Reliable operation of vacuum-assisted systems
- Simplified installation and plumbing
- Enhanced overall engine performance
Features & Benefits
- Designed for Rennen Individual Throttle Body systems
- Combines vacuum signals from multiple throttle bodies
- Provides stable vacuum reference source
- Supports MAP sensor operation
- Suitable for Rennen EFI conversion projects
- Improves engine management performance
- Ideal for performance and motorsport applications
- Precision-engineered for Porsche engine upgrades
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 964 (911) C2 1989-93
- Porsche 964 (911) C4 1989-93
- Porsche 964 (911) RS 3.6L 1991-93
- Porsche 964 (911) RS 3.8L 1991-93
Rennen ITB Black Velocity Stacks for Air-Cooled Porsche 911 - Set of 6
Precision-Engineered Velocity Stacks Designed Exclusively for Rennen ITBs
Rennen ITB Velocity Stacks have been specifically developed
for use with the innovative Rennen ITB by JSR roller barrel throttle body
system. Designed to maximise airflow efficiency and complement the advanced
induction characteristics of the Rennen ITB, these premium velocity stacks help
optimise engine breathing, improve airflow stability and support maximum
performance from your air-cooled Porsche 911 engine.
Fits:
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 964 (911) C2 1989-93
- Porsche 964 (911) C4 1989-93
- Porsche 964 (911) RS 3.6L 1991-93
- Porsche 964 (911) RS 3.8L 1991-93
Manufactured to exacting standards and available in both silver and black finishes, these velocity stacks provide the perfect finishing touch for high-performance Porsche engine builds, restomods, track cars and motorsport applications.
Available Sizes and Engine Size Combinations
Each velocity stack features an overall length of 120mm
and is available in three internal diameter options to suit a variety of engine
specifications and performance requirements:
- 2.7ltr / 3.0ltr Engine - 45mm Internal Diameter (ID)
- 3.2ltr / 3.5ltr / 3.6ltr Engine - 48mm Internal Diameter (ID)
- 4.0ltr Engine - 50mm Internal Diameter (ID)
These sizing options allow engine builders and tuners to select the most suitable intake configuration based on engine displacement, camshaft profile, intended RPM range and performance objectives.
Optimised Airflow Performance
The carefully designed bellmouth entry profile promotes smooth airflow into the throttle body, helping reduce turbulence and improve air velocity. This allows the induction system to operate more efficiently throughout the rev range while maintaining the sharp throttle response that the Rennen ITB system is renowned for.
By creating a smoother transition for incoming air, Rennen Velocity Stacks contribute to improved cylinder filling and consistent airflow delivery across all cylinders.
Premium Construction
Designed to match the quality and engineering standards of the Rennen ITB system, these velocity stacks offer exceptional durability and an outstanding motorsport-inspired appearance.
Key Features
- Designed exclusively for Rennen ITBs by JSR
- Available in silver or black finish 120mm overall length
- Available in 45mm, 48mm and 50mm internal diameters
- Precision-machined construction
- Optimised bellmouth profile for improved airflow
- Supports enhanced induction efficiency
- Complements Rennen roller barrel throttle body systems
- Suitable for road, track and race applications
- Designed for air-cooled Porsche 911 performance engines
The Perfect Addition to Your Rennen ITB Installation
Whether you are building a fast-road Porsche 911, a high-performance restomod, or a dedicated motorsport engine, Rennen ITB Velocity Stacks provide the ideal airflow solution for your induction system. Designed specifically to work with the Rennen roller barrel throttle bodies, they help deliver the performance, drivability and appearance expected from a premium Porsche performance upgrade.
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 964 (911) C2 1989-93
- Porsche 964 (911) C4 1989-93
- Porsche 964 (911) RS 3.6L 1991-93
- Porsche 964 (911) RS 3.8L 1991-93
Rennen ITB Silver Velocity Stacks for Air-Cooled Porsche 911 - Set of 6
Precision-Engineered Velocity Stacks Designed Exclusively for Rennen ITBs
Rennen ITB Velocity Stacks have been specifically developed
for use with the innovative Rennen ITB by JSR roller barrel throttle body
system. Designed to maximise airflow efficiency and complement the advanced
induction characteristics of the Rennen ITB, these premium velocity stacks help
optimise engine breathing, improve airflow stability and support maximum
performance from your air-cooled Porsche 911 engine.
Fits:
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 964 (911) C2 1989-93
- Porsche 964 (911) C4 1989-93
- Porsche 964 (911) RS 3.6L 1991-93
- Porsche 964 (911) RS 3.8L 1991-93
Manufactured to exacting standards and available in both silver and black finishes, these velocity stacks provide the perfect finishing touch for high-performance Porsche engine builds, restomods, track cars and motorsport applications.
Available Sizes and Engine Size Combinations
Each velocity stack features an overall length of 120mm
and is available in three internal diameter options to suit a variety of engine
specifications and performance requirements:
- 2.7ltr / 3.0ltr Engine - 45mm Internal Diameter (ID)
- 3.2ltr / 3.5ltr / 3.6ltr Engine - 48mm Internal Diameter (ID)
- 4.0ltr Engine - 50mm Internal Diameter (ID)
These sizing options allow engine builders and tuners to select the most suitable intake configuration based on engine displacement, camshaft profile, intended RPM range and performance objectives.
Optimised Airflow Performance
The carefully designed bellmouth entry profile promotes smooth airflow into the throttle body, helping reduce turbulence and improve air velocity. This allows the induction system to operate more efficiently throughout the rev range while maintaining the sharp throttle response that the Rennen ITB system is renowned for.
By creating a smoother transition for incoming air, Rennen Velocity Stacks contribute to improved cylinder filling and consistent airflow delivery across all cylinders.
Premium Construction
Designed to match the quality and engineering standards of the Rennen ITB system, these velocity stacks offer exceptional durability and an outstanding motorsport-inspired appearance.
Key Features
- Designed exclusively for Rennen ITBs by JSR
- Available in silver or black finish 120mm overall length
- Available in 45mm, 48mm and 50mm internal diameters
- Precision-machined construction
- Optimised bellmouth profile for improved airflow
- Supports enhanced induction efficiency
- Complements Rennen roller barrel throttle body systems
- Suitable for road, track and race applications
- Designed for air-cooled Porsche 911 performance engines
The Perfect Addition to Your Rennen ITB Installation
Whether you are building a fast-road Porsche 911, a high-performance restomod, or a dedicated motorsport engine, Rennen ITB Velocity Stacks provide the ideal airflow solution for your induction system. Designed specifically to work with the Rennen roller barrel throttle bodies, they help deliver the performance, drivability and appearance expected from a premium Porsche performance upgrade.
Porsche Electronic Fuel Injection Throttle Kits - Precision Airflow & Throttle Control
Electronic Fuel Injection (EFI) Throttle Kits upgrade the engine’s air delivery system, providing precise throttle control, improved airflow, and enhanced engine response. Designed for performance builds, engine conversions, and modernised classic Porsche applications, these kits replace restrictive or outdated throttle systems with advanced electronic throttle bodies and control hardware.
Available from Design911, Porsche EFI throttle kits are engineered to deliver smoother power delivery, sharper throttle response, and improved drivability—especially in tuned, high-performance, or track-focused engines.
What Do Electronic Fuel Injection Throttle Kits Do?
EFI throttle kits regulate the volume of air entering the engine with high precision, directly influencing power and response.
Core Functions:
- Control engine airflow electronically and accurately.
- Improve throttle response and drivability.
- Support higher airflow demands in tuned engines.
- Enable precise fuel and ignition mapping.
- Enhance overall engine efficiency and performance.
Accurate throttle control is essential for modern performance engine management.
Why Do Standard Throttle Systems Fail?
Factory or older throttle systems can become limiting or
unreliable over time, particularly in modified engines. Common issues include:
- Mechanical throttle wear or cable stretch.
- Inconsistent airflow from ageing throttle bodies.
- Restrictive designs limiting high-RPM performance.
- Poor compatibility with modern ECU tuning.
- Inadequate response for high-performance applications.
These limitations can result in sluggish response, uneven power delivery, and reduced tuning potential.
Why Upgrade to an EFI Throttle Kit?
EFI throttle kits are designed to support modern engine management and higher performance demands.
Upgrade Benefits:
- Sharper, more consistent throttle response.
- Increased airflow capacity for power upgrades.
- Improved compatibility with aftermarket ECUs.
- Enhanced drivability for road and track use.
- Ideal for engine builds, conversions, and restorations.
Upgrading to an EFI throttle kit unlocks precise control and maximises engine tuning potential.
Highlights
- Porsche electronic fuel injection throttle kits
- Precision airflow and throttle control upgrades
- Designed for tuned and performance engines
- Improved response, drivability, and power delivery
- Compatible with modern ECU management systems