Engine Valves / Guides / Springs

Valve spring seat kit - high performance. 



Fits:
Porsche 911 - 1965 to 1989
Porsche 964 - 1989 to 1994
Porsche 993 - 1994 to 1998

Our Steel Spring Seats pocket the inner spring of our Aasco High Performance Valve Springs.

Our Valve Springs are designed and manufactured to specifically fit the envelope of a Porsche application not a spring from another use. 

It operates a higher natural frequency than the original spring for racing and at the very least minimizes damage from over rev in track day situations. 

Please note
993 - must use 8mm Ti retainers and Aasco Seats

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Related, superseded, cross reference or alternative numbers for comparison.

HPSS

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Valve spring



Fits:
Porsche 993 C2 / C4 3.6L 1994-97

Click 'Zoom in' for large parts diagram.
Diagram Ref No 13.

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Related, superseded, cross reference or alternative numbers for comparison.

99310590151

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Valve spring. Porsche 993 1995-97



Fits:
Porsche 993 C2 / C4 3.6L 1994-97

Click 'Zoom in' for large parts diagram.
Diagram Ref No 13.

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Related, superseded, cross reference or alternative numbers for comparison.

99310590151

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Valve stem collect for inlet and exhaust valves
24 per engine.



Fits:
Porsche 993 1994-98

Click picture for large parts diagram.
Diagram Ref no 15.

Valve stem seals.  Sold individually x12 required per engine. 

The valve stem seal, OEM part number 993 104 111 02 (sometimes superseding 993 104 111 01), is a component for the Porsche 993 series.

These seals are installed around the valve stems and serve to regulate, not entirely block, oil flow into the combustion chamber. They wipe excess oil off the valve stems and prevent undue oil burning or plug fouling. They are applicable across various 993 configurations—including the naturally aspirated Carrera and the Turbo variants—for 1994–1998 models.

Fits:

• 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  

Why You Should Replace Them

Over time, valve stem seals, typically rubber or elastomeric, can harden, crack, or shrink, especially under high heat and engine age—which compromises their sealing effectiveness.

Visible Symptoms:

• Blue exhaust smoke, particularly upon a cold start—leftover oil seeps past hardened seals and burns in the combustion chamber.
• Increased oil consumption without noticeable external leaks, as oil is being burned rather than escaping visibly.
• Smoke or puffing at idle or after deceleration, when high vacuum draws oil past failing seals.
• Compression or misfiring issues—oil-fouled spark plugs can disrupt ignition, and carbon buildup may mimic compression loss.

Diagram ref. 8.

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

99310411102

The product you are viewing cross references to these numbers

Valve stem seals washer for inlet and exhaust valves.
12 per engine



Fits:
Porsche 993 1994-98

Click picture for large parts diagram.
Diagram Ref no 11.

Valve stem seals washer for inlet and exhaust valves.
12 per engine



Fits:
Porsche 993 1994-98

Click picture for large parts diagram.
Diagram Ref no 11.

Valve stem seals for inlet and exhaust valves
12 per engine. Sold each.



Fits:
Porsche 993 1994-98

Click 'Zoom in' for large parts diagram.
Diagram Ref no 8.

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

99310411102

The product you are viewing cross references to these numbers

Valve stem seals for inlet and exhaust valves
12 per engine.



Fits:
Porsche 993 1994-98

Click 'Zoom in' for large parts diagram.
Diagram Ref no 8.

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

99310411102

The product you are viewing cross references to these numbers