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- Porsche 911 1965-1968 2.0L / 912 SWB (F)
- Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
- 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 356 1950-55
- Porsche 356A 1955-59
- Porsche 356B 1959-63
- Porsche 356C 1963-65
Rennline Carbon Fiber Velocity Stacks (50mm Tall) |
Precision Airflow & Top-End Power for cars with Carburettors
Sold individually
The Rennline Carbon Fiber Velocity Stacks (50mm tall)
are designed to optimise intake airflow and engine performance in high-revving
applications. Constructed from ultra-lightweight carbon fibre, these 2"
(50mm) stacks enhance air velocity and resonance, allowing for improved
pressure pulse frequencies and more efficient airflow through the intake
system.
Fits:
Compared to a 2.25" trumpet, these velocity stacks deliver superior high-RPM torque and throttle response, making them ideal for motorsport and performance-focused Porsche builds. With a standard 65mm mounting hole pattern, they’re designed for easy installation on a wide range of custom and carburettor-based setups.
Each velocity stack is sold individually and built to withstand the heat, vibration, and stress of competitive driving — offering both technical performance and sleek carbon aesthetics.
What Do Velocity Stacks Do?
Velocity stacks (also known as intake trumpets) are
engineered to improve the airflow into the engine’s intake system, smoothing
the transition of air and increasing volumetric efficiency.
Core Functions:
- Increase air velocity into the throttle body or carburettor.
- Improve top-end horsepower and torque output.
- Optimise pressure waves for enhanced combustion efficiency.
- Smooth airflow and reduce turbulence at the intake mouth.
- Deliver sharper throttle response at high RPM.
In short, they allow your engine to breathe more efficiently, resulting in better performance, faster throttle response, and improved sound.
Why Do Velocity Stacks Fail or Need Replacement?
Over time, velocity stacks — particularly older aluminium or plastic types — can degrade due to heat cycling, vibration, and exposure to contaminants.
Common Causes of Failure Include:
- Cracking or delamination from extreme heat and vibration.
- Corrosion or fatigue in metal-based versions.
- Airflow restriction caused by dirt or damage.
- Poor fitment leading to air leaks or misalignment.
- Material fatigue from repeated stress during performance driving.
When velocity stacks weaken or distort, airflow becomes uneven — reducing efficiency and potentially causing imbalanced fuel-air ratios or power loss.
Why Upgrade to Rennline Carbon Fiber Velocity Stacks?
Upgrading to Rennline’s carbon fibre design provides enhanced durability, lower weight, and optimal airflow characteristics — ideal for performance-focused engines and track cars.
Key Benefits:
- Increases torque and top-end power at high RPMs.
- Lightweight carbon construction for reduced mass and improved airflow.
- Precision 50mm height ideal for performance tuning.
- Improved pressure pulse frequency for enhanced throttle response.
- Direct-fit design with 65mm mounting holes.
- Sleek carbon fibre finish adds a professional motorsport aesthetic.
Rennline’s carbon fibre stacks combine engineering precision with performance-driven design — perfect for those seeking peak airflow efficiency and style.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
M91
The product you are viewing cross references to these numbers
- Porsche 356 1950-55
- Porsche 356A 1955-59
- Porsche 356B 1959-63
- Porsche 356C 1963-65
The OE Match Ball Socket Linkage, Silver is a premium-quality replacement linkage connector designed to provide a secure, low-friction pivot connection between mechanical control linkages on compatible Porsche models. Manufactured to OE specifications for fit, strength and durability, this precision-engineered ball socket linkage ensures smooth and accurate movement of the connected linkage while maintaining reliable operation of the associated mechanical system.
Fits:
- Porsche 356 1950-55
- Porsche 356A 1955-59
- Porsche 356B 1959-63
- Porsche 356C 1963-65
Diagram Ref No 10
Manufactured from high-strength automotive-grade steel with a durable silver corrosion-resistant finish, the ball socket is engineered to withstand continual movement, vibration, changing loads and exposure to moisture and road contaminants. Precision-machined to OE dimensions, it provides direct OE-style fitment, making it ideal for replacing worn, loose or damaged linkage sockets during routine maintenance or restoration.
What This Product Does:
- Connects linkage components using a secure ball-and-socket joint.
- Allows smooth articulation and controlled movement.
- Maintains accurate operation of the connected mechanical system.
- Reduces play within the linkage assembly.
- Provides reliable retention under normal operating loads.
- Supports precise movement of associated controls.
- Restores factory linkage performance.
- Forms an essential part of the vehicle's mechanical linkage system.
Symptoms Of Wear Or Failure:
- Excessive play in the linkage.
- Loose or disconnected linkage components.
- Poor or inconsistent control operation.
- Clicking or knocking noises during movement.
- Increased resistance or stiffness in the linkage.
- Worn or enlarged socket.
- Corrosion affecting movement or fitment.
- Difficulty selecting or operating the connected mechanism.
- Reduced precision of linkage movement.
- Complete linkage separation if the socket fails.
Why Replacement Matters:
- Ball socket linkages are subjected to continual movement, vibration and mechanical loading throughout normal vehicle operation. Over time, the socket can wear, loosen or corrode, reducing the accuracy and reliability of the linkage system.
- A worn ball socket can introduce excessive free play, reduce control precision and, in severe cases, allow the linkage to become disconnected. Depending on its application, this may affect gear selection, throttle operation, heating controls or other mechanically operated systems, compromising both performance and driving confidence.
- Replacing a worn or damaged ball socket linkage with the OE Match Ball Socket Linkage restores smooth, precise operation and secure mechanical engagement. Manufactured to OE standards using premium-quality materials and a corrosion-resistant silver finish, it provides factory-style fitment, exceptional durability and dependable long-term performance, helping maintain the reliability and precision expected from your Porsche.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
90016900802
The product you are viewing cross references to these numbers
- Porsche 356 1950-55
- Porsche 356A 1955-59
- Porsche 356B 1959-63
- Porsche 356C 1963-65
The OE Match Ball Socket Linkage, Yellow is a premium-quality replacement linkage connector designed to provide a secure, low-friction pivot connection between mechanical control linkages on compatible Porsche models. Manufactured to OE specifications for fit, strength and durability, this precision-engineered ball socket linkage ensures smooth, accurate movement of the connected linkage while maintaining reliable operation of the associated mechanical system. Finished in the correct yellow colour, it is ideal for maintaining an authentic factory appearance during repairs and restorations.
Sold Each.
Fits:
- Porsche 356 1950-55
- Porsche 356A 1955-59
- Porsche 356B 1959-63
- Porsche 356C 1963-65
Diagram Ref No 10
Manufactured from high-quality automotive-grade polymer with a durable, wear-resistant construction, the ball socket is engineered to withstand continual articulation, vibration, temperature fluctuations and exposure to oils and contaminants. Precision-moulded to OE dimensions, it provides direct OE-style fitment, making it the ideal replacement for worn, loose or damaged linkage sockets.
What This Product Does:
- Connects linkage components using a secure ball-and-socket joint.
- Allows smooth articulation and controlled movement.
- Maintains accurate operation of the connected mechanical system.
- Reduces free play within the linkage assembly.
- Provides reliable retention during normal operation.
- Supports precise movement of associated controls.
- Restores factory linkage performance.
- Forms an essential part of the vehicle's mechanical linkage system.
Symptoms Of Wear Or Failure:
- Excessive play in the linkage assembly.
- Loose or disconnected linkage components.
- Inconsistent or imprecise control operation.
- Clicking or knocking noises during movement.
- Increased stiffness or resistance in the linkage.
- Cracked or worn socket housing.
- Difficulty selecting or operating the connected mechanism.
- Excessive movement caused by socket wear.
- Reduced responsiveness of the linkage.
- Complete linkage separation if the socket fails.
Why Replacement Matters:
- Ball socket linkages are subjected to continual movement, vibration and repeated mechanical loads throughout their service life. Over time, the socket can wear, become brittle or lose its ability to securely retain the mating ball joint, resulting in excessive free play or eventual separation.
- A worn or damaged ball socket can reduce the accuracy and reliability of the linkage system, affecting the operation of the associated controls. If left unresolved, complete failure of the socket can disconnect the linkage entirely, preventing correct operation of the connected component.
- Replacing a worn or damaged ball socket with the OE Match Ball Socket Linkage restores smooth, precise movement and dependable mechanical engagement. Manufactured to OE standards using premium-quality materials, it provides factory-style fitment, excellent wear resistance and long-lasting durability, ensuring the reliable operation and originality expected from your Porsche.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
90016900802
The product you are viewing cross references to these numbers
- Porsche 356 1950-55
- Porsche 356A 1955-59
- Porsche 356B 1959-63
- Porsche 356C 1963-65
The OE Match Ball Socket Linkage, Silver is a premium-quality replacement linkage connector designed to provide a secure and precise pivot connection between mechanical linkage components on compatible Porsche models. Manufactured to OE specifications for fit, strength and durability, this precision-engineered ball socket linkage ensures smooth articulation and accurate transfer of movement between connected components, helping maintain the correct operation of the vehicle's mechanical control systems.
Fits:
- Porsche 356 1950-55
- Porsche 356A 1955-59
- Porsche 356B 1959-63
- Porsche 356C 1963-65
Diagram Ref No 11
Manufactured from high-strength automotive-grade steel with a durable silver corrosion-resistant finish, the ball socket linkage is engineered to withstand continual movement, vibration, varying loads and exposure to moisture, dirt and road contaminants. Precision-machined to OE dimensions, it provides direct OE-style fitment, making it ideal for replacing worn, damaged or loose linkage connectors during routine servicing, repairs or restoration.
What This Product Does:
- Connects mechanical linkage components using a secure ball-and-socket joint.
- Allows smooth articulation throughout the linkage's range of movement.
- Maintains accurate transfer of mechanical motion.
- Reduces free play within the linkage assembly.
- Provides secure retention under normal operating conditions.
- Supports smooth and precise control operation.
- Restores factory linkage performance.
- Forms an essential part of the vehicle's mechanical linkage system.
Symptoms Of Wear Or Failure:
- Excessive free play within the linkage.
- Loose or disconnected linkage components.
- Poor or inconsistent operation of the connected control.
- Clicking, knocking or rattling noises during movement.
- Increased resistance or stiffness in the linkage.
- Worn or enlarged ball socket.
- Corrosion affecting movement or fitment.
- Reduced precision of linkage operation.
- Difficulty operating the connected mechanism.
- Complete linkage separation if the socket fails.
Why Replacement Matters:
- Ball socket linkages are subjected to continual articulation, vibration and mechanical loading throughout normal vehicle operation. Over time, the socket can wear, loosen or corrode, reducing its ability to securely retain the mating ball joint and maintain accurate movement.
- A worn linkage socket can introduce excessive free play, reduce control precision and, in severe cases, allow the linkage to disconnect completely. Depending on its application, this may affect gear selection, throttle controls, heating controls or other mechanical systems, compromising both vehicle performance and driver confidence.
- Replacing a worn or damaged linkage with the OE Match Ball Socket Linkage restores secure mechanical engagement and smooth, precise movement. Manufactured to OE standards using premium-quality materials and a corrosion-resistant silver finish, it provides factory-style fitment, exceptional durability and dependable long-term reliability, ensuring the performance and precision expected from your Porsche.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
90016901302
The product you are viewing cross references to these numbers