Please wait…

Please wait while we process your order,
do not press the back button…

Original Porsche Part Genuine Porsche part 99310542101

Code: 99310542101

Genuine Porsche part

Original Porsche Part

Additional information:

• This part is brand new and unused.
• Please verify that it is 100% suitable for your specific vehicle before purchase to ensure compatibility.

Before purchasing thoroughly check part to confirm compatibility.

Related products

4 4 4 4

Engine cylinder head exhaust valve. Porsche 993 C2 / C4 1994-95

99310541901/1

Product Information

Engine cylinder head exhaust valve. Pre varioram engine cars
The OE Match exhaust valve is a precision engine component designed for Porsche 911 (993) Carrera models equipped with early 3.6L engines. It is installed in the cylinder head and forms part of the valve train responsible for controlling the flow of exhaust gases from the combustion chamber to the exhaust system.
Sold individually, 6 required per vehicle

Fits:
Porsche 993 C2 / C4 3.6L 1993 - 1995
* with Engine codes: M64.05 / M64.06 / M64.07 / M64.08

Diagram Ref No 10

The OE Match version of part number 99310541901 is designed for pre-Varioram Porsche 993 engines used in early Carrera models. It is engineered with the correct stem diameter, valve head size and material specification to withstand the extreme temperatures and stresses experienced in high-performance air-cooled engines.

The exhaust valve regulates the release of burnt gases from the combustion chamber. When opened at the correct time by the camshaft, it allows exhaust gases to exit the cylinder and enter the exhaust system, preparing the chamber for the next intake cycle.

Maintaining properly functioning valves is essential for efficient combustion, engine power and reliable operation.

Exhaust valves operate under extremely high temperatures and continuous mechanical stress. Over time they may wear, warp or suffer from carbon buildup, which can lead to compression loss, poor engine performance or valve train noise. Replacing worn valves during engine service or rebuild ensures proper combustion sealing and reliable engine operation.

Consider replacing the exhaust valve if you notice:
• Loss of compression or engine power
• Excessive valve train noise
• Burnt or worn valve surfaces
• During cylinder head rebuild or engine overhaul

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

99310541901

99310541901

3311.239

The product you are viewing cross references to these numbers

Engine cylinder head inlet valve. Porsche 993 C2 / 993 C4 / 993 Turbo

99310540902/1

Product Information

Engine Cylinder Head Inlet Valve.
The OE Match Engine Cylinder Head Inlet Valve is a high-quality replacement valvetrain component designed to regulate the flow of air and fuel into the combustion chamber. Manufactured to OE specifications for fit, precision and durability, this inlet valve is essential for maintaining efficient combustion, engine performance and long-term reliability.

Fits:

Porsche 993 (911) C2 1994-97
Porsche 993 (911) C4 1994-97
Porsche 993 (911) TURBO 1994-96
Porsche 993 (911) TURBO S 1994-97

Diagram Ref No 9

Constructed from premium-grade materials engineered to withstand continuous operation and high engine temperatures, the inlet valve works in conjunction with the camshaft, valve springs, valve guides and cylinder head assembly to control intake airflow with precise timing. Proper valve operation ensures optimal cylinder filling, efficient combustion and the responsive performance expected from a Porsche engine.

What This Product Does:

Controls the intake of air and fuel into the combustion chamber.
Opens and closes in precise synchronisation with the engine cycle.
Maintains an effective seal during compression and combustion.
Supports efficient airflow and cylinder filling.
Helps maximise engine power and throttle response.
Contributes to fuel economy and emissions control.
Forms a critical part of the engine valvetrain system.

Symptoms Of Wear Or Failure:

Reduced engine power and acceleration.
Rough idle or uneven engine operation.
Engine misfires.
Poor throttle response.
Increased fuel consumption.
Low compression in the affected cylinder.
Difficulty starting the engine.
Ticking or tapping noises from the cylinder head.
Engine management warning lights or fault codes.
Failed compression or leak-down test results.

Why Replacement Matters:

Inlet valves operate continuously under demanding conditions and are subjected to thousands of opening and closing cycles every minute. Over time, exposure to heat, combustion deposits and mechanical wear can cause valves to become worn, bent, burnt, carbon-contaminated or develop sealing issues.
A damaged inlet valve can restrict airflow into the combustion chamber, reducing combustion efficiency and negatively affecting engine performance. If left unresolved, valve-related problems can lead to compression loss, increased fuel consumption and potential damage to valve seats, cylinder heads and other internal engine components.
Replacing a worn or damaged inlet valve restores proper airflow, improves combustion efficiency and helps maintain optimal engine performance. An OE Match replacement provides factory-style fitment, precision manufacturing and long-term durability, ensuring reliable operation and helping protect your Porsche engine from premature wear and costly repairs.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

99310540902

99310540902

993.105.409.02

3310.239

854429-6

The product you are viewing cross references to these numbers

Engine cylinder head exhaust valve. Porsche 993 C2 / C4 1996-98

99310541906/1

Product Information

Exhaust Valve - Varioram Engines
Sold each - 6 required per car

Maintain the performance, efficiency and reliability of your Porsche 993 Varioram engine with this OE Match Exhaust Valve. Designed specifically for Porsche 993 Varioram engines including M64.21, M64.22, M64.23 and M64.24 engine variants, this exhaust valve plays a critical role in the combustion process by allowing spent exhaust gases to exit the combustion chamber efficiently.

Fits:

Porsche 993 (911) C2 1996-97
Porsche 993 (911) C4 1996-97
Porsche 993 (911) RS 1996-97
Porsche 993 (911) C2S 1996-97
Porsche 993 (911) C4S 1996-97

Diagram Ref No 10

Operating under extreme temperatures and pressures, exhaust valves are among the hardest-working components within the engine. During every combustion cycle, they must withstand intense heat while maintaining an effective seal against the valve seat to preserve compression, power output and engine efficiency.

Manufactured to OE Match specifications, this exhaust valve is ideal for engine rebuilds, cylinder head refurbishment, top-end overhauls and preventative maintenance projects.

Technical Specification
Valve Head Diameter: 43.50 mm
Valve Stem Diameter: 8.00 mm
Valve Shaft Length: 109.00 mm
Valve Seat Angle: 45°
Suitable for Porsche 993 Varioram engines: M64.21 M64.22 M64.23 M64.24

What Does the Exhaust Valve Do?

The exhaust valve is responsible for controlling the exit of combustion gases from the cylinder.

Its primary functions include:

Releasing burnt exhaust gases
Maintaining combustion chamber sealing
Supporting efficient engine breathing
Preserving compression
Assisting engine performance
Supporting fuel efficiency
Maintaining smooth engine operation

Correct exhaust valve operation is essential for maintaining the power and responsiveness expected from the Porsche 993 Varioram engine.

Why Do Exhaust Valves Fail?

Exhaust valves are exposed to some of the harshest operating conditions within the engine.

Common causes of failure include:

Extreme heat exposure
Valve seat wear
Carbon build-up
High mileage wear
Detonation damage
Valve guide wear
Overheating

Over time, valves can become worn, burnt, pitted or damaged, reducing their ability to seal effectively.

Symptoms of a Worn or Damaged Exhaust Valve

Common warning signs include:

Reduced engine compression
Loss of power
Rough idle
Increased exhaust emissions
Misfires
Excessive oil consumption
Poor throttle response
Unusual engine noise

In severe cases, a burnt valve can significantly affect engine performance and drivability.

When Should Exhaust Valves Be Replaced?

Replacement is recommended when:

Carrying out a cylinder head rebuild
Performing a top-end engine overhaul
Valve seat damage is present
Compression loss is identified
Burnt valves are discovered
Valve stem wear exceeds specifications
Rebuilding a high-mileage engine
Completing a full engine restoration

Professional engine builders routinely inspect and measure all valves during rebuild work.

Why Replacement Matters

A worn exhaust valve can compromise engine performance, reliability and efficiency.

Benefits of replacement include:

Restored compression
Improved power delivery
Better engine efficiency
Smoother operation
Improved combustion quality
Reduced emissions
Increased engine reliability
Long-term engine protection

Replacing worn valves during a rebuild helps ensure the longevity of expensive engine components.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

99310541906

99310541906

993.105.419.06

3342.239

864428-6

99310541943

The product you are viewing cross references to these numbers

Engine cylinder head inlet valve. Porsche 911 (993) 3.8 Carrera RS

99310540942/1

Product Information

Engine Cylinder Head Inlet Valve.

The OE Match Engine Cylinder Head Inlet Valve is a precision replacement valvetrain component for the Porsche 911 (993) 3.8 Carrera RS. It controls the flow of intake air and fuel into the combustion chamber and provides an essential sealing surface when the valve closes against its seat.

Fits:

Porsche 911 (993) 3.8 Carrera RS 1995-96 (M64.20)

Valve type: Inlet valve;
Valve head diameter: 51,50 mm;
Valve stem diameter: 8,00 mm;
Total length: 111,10 mm;
Valve seat angle: 45°;
Groove type: 3 groove;

Diagram Ref No 9

During the intake stroke, the valve opens to allow the cylinder to fill. It then closes against the valve seat so the combustion chamber can build and retain the compression required for efficient combustion.

Correct inlet valve condition, alignment and seating are essential for strong cylinder filling, consistent compression, smooth engine operation and reliable performance.

What This Product Does:

Controls the intake of air and fuel into the combustion chamber.
Opens during the intake stroke to allow the cylinder to fill.
Closes against the valve seat to seal the combustion chamber.
Helps maintain correct cylinder compression.
Supports efficient airflow and combustion.
Helps maintain strong throttle response and engine performance.
Works with the valve guide, valve seat, spring and associated valvetrain components.
Replaces an inlet valve that has become bent, burnt, pitted or excessively worn.
Helps restore correct cylinder-head operation during an engine rebuild.

The valve must move smoothly within the valve guide and seat evenly around its circumference. Damage or wear that prevents complete seating can allow compression to escape and reduce engine efficiency.

Symptoms Of Wear Or Failure:

Possible symptoms include:
Low or uneven cylinder compression.
Engine misfires.
Rough or unstable idle.
Reduced engine power.
Poor acceleration or throttle response.
Difficult starting.
Increased fuel consumption.
Uneven engine running.
Ticking or abnormal valvetrain noise.
Poor compression-test results.
Leakage through the intake system during a leak-down test.
Pitting or erosion of the valve face.
Heavy carbon deposits around the valve.
Bent or damaged valve stem.
Excessive valve-stem wear.
Failure of the valve to seal correctly against its seat.

A leaking inlet valve can allow compression pressure to escape back into the intake tract rather than remaining within the combustion chamber.

Why Replacement Matters:
The inlet valve plays a direct role in both filling and sealing the cylinder. If the valve becomes worn, bent, damaged or unable to seat correctly, combustion efficiency and cylinder compression can be affected.

Poor valve sealing can result in:

Reduced engine power.
Rough running and misfires.
Poor starting.
Uneven cylinder performance.
Reduced combustion efficiency.
Increased fuel consumption.
Further wear to the valve and valve seat.

Replacing a defective inlet valve helps restore correct airflow, compression and combustion-chamber sealing.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

99310540942

99310540942

3284.032

854449

854449-6

The product you are viewing cross references to these numbers

Engine cylinder head exhaust valve. Porsche 911 (993) 3.8 Carrera RS

99310541943/1

Product Information

Engine Cylinder Head Exhaust Valve.

The OE Match Engine Cylinder Head Exhaust Valve is a precision replacement valvetrain component for the Porsche 911 (993) 3.8 Carrera RS. It controls the release of burnt combustion gases from the cylinder and provides an essential seal against the valve seat when closed.

Fits:

Porsche 911 (993) 3.8 Carrera RS 1995-96 (M64.20)

Diagram Ref No 10

During the exhaust stroke, the valve opens to allow combustion gases to leave the cylinder and flow into the exhaust system. It then closes firmly against the valve seat, helping the combustion chamber retain the compression required during the following engine cycle.

Because exhaust valves are directly exposed to extremely hot combustion gases, they operate under demanding thermal and mechanical conditions. Correct valve condition, alignment and seating are therefore essential for maintaining compression, efficient combustion and reliable engine performance.

What This Product Does:

Controls the release of exhaust gases from the combustion chamber.
Opens during the exhaust stroke to allow burnt gases to leave the cylinder.
Closes against the valve seat to maintain combustion-chamber sealing.
Helps maintain correct cylinder compression.
Supports efficient combustion and engine performance.
Helps maintain consistent power delivery and smooth engine operation.
Works with the valve guide, valve seat, valve spring and associated valvetrain components.
Replaces an exhaust valve that has become burnt, bent, pitted or excessively worn.
Helps restore correct cylinder-head operation during an engine rebuild.

For correct operation, the valve must move smoothly within its guide and contact the valve seat evenly around its circumference. Wear or damage that prevents complete seating can allow compression and hot combustion gases to escape.

Symptoms Of Wear Or Failure:
Possible symptoms include:

Low or uneven cylinder compression.
Engine misfires.
Rough or unstable idle.
Loss of engine power.
Poor acceleration or throttle response.
Difficult starting.
Increased fuel consumption.
Irregular exhaust note.
Ticking or abnormal valvetrain noise.
Poor compression-test results.
Leakage through the exhaust during a cylinder leak-down test.
Pitting or erosion of the valve face.
Burnt or damaged valve seating surface.
Bent or damaged valve stem.
Excessive valve-stem wear.
Heavy carbon deposits.
Failure of the valve to seal correctly against its seat.

A leaking exhaust valve allows combustion pressure to escape into the exhaust port rather than remaining within the cylinder, reducing compression and engine efficiency.

Why Replacement Matters:
The exhaust valve operates in one of the most thermally demanding areas of the engine. Every combustion cycle exposes the valve head and seating surface to extremely hot exhaust gases while the valve repeatedly opens and closes at high speed.

Over time, the valve can suffer from:

Valve-face erosion.
Burning or pitting.
Carbon build-up.
Valve-stem wear.
Mechanical distortion.
Overheating.
Damage caused by incorrect valve seating.
Wear associated with excessive valve-guide clearance.

Once the valve can no longer seal correctly, cylinder compression may fall and engine performance can deteriorate.

Replacing a defective exhaust valve helps restore:

Correct combustion-chamber sealing.
Cylinder compression.
Smooth engine operation.
Consistent power delivery.
Efficient exhaust-gas control.
Correct valvetrain operation.
Long-term cylinder-head reliability.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

99310541943

99310541943

The product you are viewing cross references to these numbers

Enter your VAT number here and click Verify:

Original Porsche Part Genuine Porsche part 99310542101