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- 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
With TÜV/EEC approval

Fits:
Porsche 911 2.7ltr - 1974 to 1976
Porsche 911 SC 3.0ltr - 1978 to 1983
Porsche 911 3.2ltr - 1984 to 1989
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91122092511
The product you are viewing cross references to these numbers
- Porsche 911 1965-1968 2.0L / 912 SWB (F)
- Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
Complete with Chrome tail pipe. Painted mild steel 2 in / 1 outlet

Fits:
Porsche 911 1965-73 Non Impact Bumper Cars
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91111102505
The product you are viewing cross references to these numbers
- Porsche 911 1965-1968 2.0L / 912 SWB (F)
- Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
With TÜV/EEC approval.

Fits:
Porsche 911 T/E/S 2.0L-2.4L 1964-73
Can be used with SSI or standard straight through heat exchanger systems
2 x Exhaust gaskets required Part No. 90111119300
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91122092210
The product you are viewing cross references to these numbers
- Porsche 911 1965-1968 2.0L / 912 SWB (F)
- Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
With TÜV/EEC approval.

Fits:
Porsche 911 T/E/S 2.0L-2.4L 1964-73
Can be used with SSI or standard straight through heat exchanger systems
2 x Exhaust gaskets required Part No. 90111119300
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91122092210OE
The product you are viewing cross references to these numbers
- Porsche 911 1965-1968 2.0L / 912 SWB (F)
- Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
With TÜV/EEC approval

Fits:
Porsche 911 1965-73 Non Impact Bumper Cars
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91122092510
The product you are viewing cross references to these numbers
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
Replacement rear Exhaust. Ø60mm Outlet pipe With TÜV/EEC approval

Fits:
Porsche 911 1974-83
Only to be used with SSI or straight through heat exchanger systems
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91122092211
The product you are viewing cross references to these numbers
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
Replacement rear Exhaust. Ø60mm Outlet pipe With TÜV/EEC approval

Fits:
Porsche 911 1974-83
Only to be used with SSI or straight through heat exchanger systems
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91122092211OE
The product you are viewing cross references to these numbers
- Porsche 911 1965-1968 2.0L / 912 SWB (F)
Exhaust muffler with twin inlet & single, grey painted, Ø57 mm tailpipe and chrome tailpipe. Early OEM style heat shield
Standard replacement rear Exhaust for Non Impact bumper cars.

Fits:
Porsche 911 2.0ltr - August 1965 to July 1966
Mild steel tailpipe with chrome, flat rolled trim
Heat protection and noise reduction shield top and bottom
2 x Exhaust gaskets required Part No. 90111119300
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91111102500
The product you are viewing cross references to these numbers
Standard Silencers
2-In, 1-Out Standard Exhaust Silencer – Classic Porsche Performance, Perfected
A 2-in, 1-out exhaust silencer is a key component in your Porsche’s exhaust system, responsible for reducing noise, managing back pressure, and optimising exhaust gas flow. This design, featuring dual inlets and a single outlet, balances performance with refinement — maintaining that unmistakable Porsche exhaust note while ensuring smooth, efficient engine operation.
At Design911, we offer a range of high-quality 2-in, 1-out silencers crafted from premium-grade stainless steel for exceptional durability, corrosion resistance, and performance. Designed as direct-fit replacements, these silencers deliver the same balance of tone, performance, and longevity as your original system, making them ideal for restorations and daily-driven Porsche models alike.
Each unit is engineered for optimal exhaust flow, ensuring improved throttle response, reduced restriction, and enhanced engine efficiency without compromising drivability or noise regulations.
What Does a 2-In, 1-Out Exhaust Silencer Do?
A silencer (or muffler) manages exhaust gases leaving the engine, reducing noise and maintaining back pressure to preserve engine performance.
Core Functions:
- Reduces exhaust noise while preserving Porsche’s signature tone.
- Manages back pressure to optimise engine efficiency and torque.
- Directs exhaust gases through tuned chambers for smooth flow.
- Aids emissions compliance and exhaust temperature regulation.
- Contributes to overall drivability and comfort.
In a 2-in, 1-out configuration, exhaust gases from dual banks merge into a single outlet, ensuring balanced pressure and efficient flow for flat-six Porsche engines.
Why Do Exhaust Silencers Fail?
Exhaust silencers operate under extreme heat, pressure, and exposure to moisture and contaminants. Over time, these conditions cause deterioration and performance loss.
Common Causes of Failure Include:
- Corrosion from moisture and road salt.
- Cracked welds or seams from vibration and heat cycling.
- Internal baffle wear causing excessive noise or reduced back pressure.
- Blockages or soot build-up restricting gas flow.
- Damaged mounting points or hangers.
Typical symptoms include louder exhaust noise, vibration, rattling, or loss of performance, signalling the need for replacement to maintain both performance and safety.
Why Replace Silencer?
Replacing a worn or damaged silencer with a precision-engineered 2-in, 1-out unit restores your Porsche’s performance, tone, and efficiency.
Key Benefits:
- Restores proper exhaust flow and pressure balance.
- Reduces noise while maintaining the Porsche character.
- Improves throttle response and low-end torque.
- Constructed from corrosion-resistant stainless steel.
- Direct-fit compatibility for classic and modern Porsche models.
- Ideal for restoration, daily driving, or performance maintenance.
A quality replacement silencer ensures that your Porsche performs and sounds exactly as intended — reliable, refined, and responsive.
Highlights:
- 2-in, 1-out exhaust silencers for Porsche models.
- Precision-engineered for balance between tone and performance.
- Durable stainless steel construction for long service life.
- Reduces noise and maintains optimal back pressure.
- Perfect for restoration or performance maintenance.
- Direct-fit installation for Porsche 911 and related models.