Breather Pipes

Fits:
Porsche 993 Turbo 1994 - 1998
Diagram ref no 52
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99320714351
The product you are viewing cross references to these numbers
- Porsche 993 (911) TURBO 1994-96
- Porsche 993 (911) TURBO S 1994-97


Fits:
Porsche 993 Carrera 2 / Carrera 4 >>1995
Engine type: 6405 / 6406 / 6407 / 6408
Click 'Zoom in' for large parts diagram.
Diagram ref no 37
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99320715082
The product you are viewing cross references to these numbers
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97

Fits:
Porsche 993 Carrera 2 / Carrera 4 >>1995
Engine type: 6405 / 6406 / 6407 / 6408
Click 'Zoom in' for large parts diagram.
Diagram ref no 37
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99320715082
The product you are viewing cross references to these numbers
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97


Fits:
Porsche 993 C2 / C4 / RS 1995-98
Click 'Zoom in' for large parts diagram.
Diagram ref no 54
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99320715102
The product you are viewing cross references to these numbers
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) RS 1994-97
- Porsche 993 (911) C2S 1994-97
- Porsche 993 (911) C4S 1994-97

Fits:
Porsche 993 C2 / C4 / Carrera RS 1994 - 1995
Diagram Ref No 59
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99320715202
The product you are viewing cross references to these numbers
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) RS 1994-97
- Porsche 993 (911) C2S 1994-97
- Porsche 993 (911) C4S 1994-97
Fits:
Porsche 993 C2 / C4 - 1994 to 1998
Diagram ref no 54
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99320715104
The product you are viewing cross references to these numbers
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) RS 1994-97
- Porsche 993 (911) C2S 1994-97
- Porsche 993 (911) C4S 1994-97

Fits:
Porsche 993 C2 / C4 / RS 1994 to 1998
Porsche 993 turbo - 1994 to 1998
Click 'Zoom in' for large parts diagram.
Diagram ref no 29
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99320714601
The product you are viewing cross references to these numbers
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) RS 1994-97
- Porsche 993 (911) C2S 1994-97
- Porsche 993 (911) C4S 1994-97
- Porsche 993 (911) TURBO 1994-96
- Porsche 993 (911) GT2 1994-97
- Porsche 993 (911) TURBO S 1994-97
Fits:
Porsche 993 C2 / C4 / RS 1995-98
Diagram ref no 54
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99320715102
The product you are viewing cross references to these numbers
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) RS 1994-97
- Porsche 993 (911) C2S 1994-97
- Porsche 993 (911) C4S 1994-97
Fits:
Porsche 993 C2 / C4 3.6L 1994-95
Diagram ref no 52.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99320714301
The product you are viewing cross references to these numbers
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97


Fits:
Porsche 993 C2 / C4 3.6L 1994-95
Click 'Zoom in' for large parts diagram.
Diagram Ref No 52.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99320714301
The product you are viewing cross references to these numbers
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97
Fits:
Porsche 993 C2 / C4 3.6L 1996-98
Porsche 993 Carrera RS 3.75L 1995-96
Diagram Ref No 52.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99320714303
The product you are viewing cross references to these numbers
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) RS 1994-97

Fits:
Porsche 993 C2 / C4 3.6L 1996-98
Porsche 993 Carrera RS 3.75L 1995-96
Click picture for large parts diagram.
Diagram Ref No 52.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99320714303
The product you are viewing cross references to these numbers
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) RS 1994-97


Fits:
Porsche 993 Carrera 2 - 1994 to 1995
Porsche 993 Carrera 4 - 1994 to 1995
For engine codes
6405 / 6406 / 6407 / 6408
Click 'Zoom in' for large parts diagram.
Diagram ref no 54
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99320715104
The product you are viewing cross references to these numbers
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97


Fits:
Porsche 911 - 1978 to 1989
Porsche 964 - 1989 to 1994
Porsche 993 - 1994 to 1998
Porsche 986 Boxster - 1997 to 2004
Porsche 996 - 1997 to 2005
Porsche 997.1 - 2005 to 2008
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99951255400
The product you are viewing cross references to these numbers
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster 986 2.7L 2003-04
- Porsche Boxster S 986 3.2L 2003-04
- 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
- Porsche 964 (911) TURBO 3.3L 1991-93
- Porsche 964 (911) TURBO 3.6L 1991-93
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) RS 1994-97
- Porsche 993 (911) C2S 1994-97
- Porsche 993 (911) C4S 1994-97
- Porsche 993 (911) TURBO 1994-96
- Porsche 993 (911) GT2 1994-97
- Porsche 993 (911) TURBO S 1994-97
- Porsche 996 C2 3.4L 1997-08/01
- Porsche 996 C4 3.4L 1997-08/01
- Porsche 996 C2 3.6L 09/01-2005
- Porsche 996 C4 3.6L 09/01-2005
- Porsche 996 C4S 3.6L 09/01-2005
- Porsche 996 TURBO 2000-05
- Porsche 996 GT2 2001-05
- Porsche 996 GT3 MKI 1999-02
- Porsche 996 GT3 MKII 2003>>
- Porsche 996 GT3 RS 2003-04
- Porsche 997 MK1 Carrera 2 3.6L 2005-08
- Porsche 997 MK1 Carrera 2S 3.8L 2005-08
- Porsche 997 MK1 Carrera 4 3.6L 2005-08
- Porsche 997 MK1 Carrera 4S 3.8L 2005-08
- Porsche 997 MK1 TURBO 2007-09
- Porsche 997 MK1 GT3 2007-09
- Porsche 997 MK1 GT2 2007-09
The 99320714903 is a vent or breather hose - also referred to as an oil tank breather hose or crankcase vent hose - specifically designed for Porsche 911 “993” models. Its primary role is to equalize pressure within the oil tank and crankcase by safely channeling oil vapors and gases. This prevents excessive pressure that could cause oil leaks, foaming, or oil being forced past seals and gaskets, while also helping manage emissions by directing vapors correctly.
Fits:
Porsche 993 Carrera 2 / Carrera 4 1994 - 1997
Porsche 993 Carrera S / Carrera 4S 1994 - 1997
Porsche 993 turbo / GT2 1994 - 1997
Diagram ref no 33
Replacing this hose matters for several reasons:
• If the hose ages, cracks, gets brittle, or is blocked, it can’t vent properly. This may lead to pressure build-up in the oil tank/crankcase
• A faulty hose can cause oil leaks through seals or gaskets, or force oil out of vent points
• It can lead to poor engine performance or oil foaming, which in turn risks oil starvation or damage, especially under heavy load or high temperature
• Emissions issues may result: the engine may throw codes, or oil vapors may be vented where they shouldn’t, failing emission checks
• For older cars, these hoses degrade over time (rubber/hoses hardened by heat, oil exposure); preventative replacement helps avoid breakdowns.
This part often supersedes earlier versions (99320714901 and 99320714902), making it the updated replacement in many cases.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99320714903
The product you are viewing cross references to these numbers
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) RS 1994-97
- Porsche 993 (911) C2S 1994-97
- Porsche 993 (911) C4S 1994-97
- Porsche 993 (911) TURBO 1994-96
- Porsche 993 (911) GT2 1994-97
- Porsche 993 (911) TURBO S 1994-97


Fits:
Porsche 993 Carrera / Carrera RS 1996>>
Click 'Zoom in' for large parts diagram.
Diagram ref no 37
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99320715002
The product you are viewing cross references to these numbers
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) RS 1994-97
- Porsche 993 (911) C2S 1994-97
- Porsche 993 (911) C4S 1994-97
Engine Oil System Breather Pipes – Precision Ventilation for Porsche Performance
The engine oil breather system plays a crucial role in maintaining internal pressure balance, oil circulation, and overall engine health. The breather pipes allow gases, vapour, and excess pressure to escape from the crankcase, preventing oil contamination, leaks, and performance loss.
At Design911, we supply a comprehensive selection of oil system breather pipes and ventilation components designed for Porsche engines across all generations. Built from high-quality, oil- and heat-resistant materials, our breather pipes are engineered for long service life, durability, and a direct-fit installation — ensuring your Porsche continues to run smoothly under all driving conditions.
Whether you’re maintaining a daily-driven 911 or restoring a classic air-cooled model, our breather pipes help safeguard your engine’s lubrication system and performance.
What Do Engine Oil Breather Pipes Do?
Oil breather pipes are essential to the proper function of your Porsche’s oil system. They manage pressure and vapour within the crankcase, ensuring oil flow remains consistent and clean.
Core Functions:
- Vent
crankcase pressure to maintain oil system stability.
- Prevent
oil leaks by balancing internal engine pressure.
- Reduce
contamination by separating oil vapour from blow-by gases.
- Improve efficiency by maintaining clean airflow and optimal oil return.
Properly functioning breather pipes ensure your Porsche’s engine stays free of excessive pressure and sludge build-up, promoting smooth operation and extended engine life.
Why Do Oil Breather Pipes Fail?
Over time, breather pipes are exposed to intense heat, oil vapour, and pressure changes that can cause deterioration and leaks.
Common Causes of Failure Include:
- Cracking
or hardening of rubber or plastic due to heat cycles.
- Oil
residue build-up, leading to restricted airflow.
- Blockages
caused by sludge or carbon deposits.
- Loose
fittings or seals allowing air or oil leaks.
- Age-related wear in high-mileage or older engines.
Symptoms of failing breather pipes include oil leaks, rough idling, increased crankcase pressure, or smoke from the exhaust — all signs that the ventilation system is compromised.
Why Replace with Precision-Engineered Breather Pipes?
Replacing worn or damaged breather pipes is essential for maintaining optimal oil pressure and engine performance. Our precision-fit, high-durability replacements are designed to restore proper ventilation and prevent costly oil-related issues.
Key Benefits:
- Restores optimal crankcase ventilation and pressure control.
- Prevents oil leaks and blow-by contamination.
- Improves idle stability and engine efficiency.
- Constructed from heat- and oil-resistant materials.
- Direct-fit
compatibility for classic and modern Porsche engines.
- Ideal for regular maintenance or full engine rebuilds.
These parts are engineered to deliver long-term reliability and protect your Porsche’s engine from unnecessary wear.
Highlights:
- Precision-engineered oil breather pipes for Porsche engines.
- High-quality
materials for maximum durability and heat resistance.
- Direct-fit
replacements ensuring leak-free performance.
- Improves oil system efficiency and longevity.
- Compatible with air-cooled and water-cooled Porsche models.
- Perfect for rebuilds, maintenance, or performance upgrades.