Engine Valves / Guides / Springs
Fits:
Porsche 993 - 1994 to 1998
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.
Kit includes
High performance valve spring x 12
High performance valve spring seat x 12
High performance 8mm titanium valve spring retainer disc x 12
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
HP10T8HPSSKIT
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 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Related, superseded, cross reference or alternative numbers for comparison.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
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
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.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99310411102
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 - 1994 to 1998
8mm Porsche 911 Titanium Retainers for 993 1995-1998 for 8mm valves.
Please note
Must be used in conjunction with Aasco HP109-Valve Springs and HPSS Spring Seats.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
HP10T8
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 911 (993) 3.8 Carrera RS 1995-96 (M64.20)
Click 'Zoom in' for large parts diagram.
Diagram Ref No 10
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99310541943
The product you are viewing cross references to these numbers
- Porsche 993 (911) RS 1994-97

Fits:
Porsche 911 (993) 3.8 Carrera RS 1995-96 (M64.20)
Click 'Zoom in' for large parts diagram.
Diagram Ref No 10
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99310541943
The product you are viewing cross references to these numbers
- Porsche 993 (911) RS 1994-97
Pre varioram engine cars

Fits:
Porsche 993 C2/C4 3.6L 1993-95
911 (993) 3.6 L M64.05 / M64.06 / M64.07 / M64.08
Click 'Zoom in' for large parts diagram.
Diagram Ref No 10.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99310541901
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) C2S 1994-97
- Porsche 993 (911) C4S 1994-97

Fits:
Porsche 993 C2/C4 3.6L 1996-98
911 (993), 3.6 Carrera M64.21 / M64.22 / M64.23 / M64.24
Valve head diameter 43,50 mm
Valve stem diameter 8,00 mm
Valve shaft length 109,00 mm
Valve seat angle 45 °
Click 'Zoom in' for large parts diagram.
Diagram Ref No 10.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99310541906
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 Carrera RS 1995-98
Click 'Zoom in' for large parts diagram.
Diagram ref no 10
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99310541983
The product you are viewing cross references to these numbers
- Porsche 993 (911) RS 1994-97

Fits:
Porsche 993 Carrera RS - 1995 to 1998
Click 'Zoom in' for large parts diagram.
Diagram ref no 10
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99310541983
The product you are viewing cross references to these numbers
- Porsche 993 (911) RS 1994-97


Fits:
Porsche 993 Turbo 3.6L 1995-98 (M64.60)
Click 'Zoom in' for large parts diagram.
Diagram Ref No 10.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99310541952
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 Turbo 3.6L 1995-98 (M64.60)
Click 'Zoom in' for large parts diagram.
Diagram Ref No 10.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99310541952
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 911 (993) 3.8 Carrera RS 1995-96 (M64.20)
Click 'Zoom in' for large parts diagram.
Diagram Ref No 9
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99310540942
The product you are viewing cross references to these numbers
- Porsche 993 (911) RS 1994-97

Fits:
Porsche 911 (993) 3.8 Carrera RS 1995-96 (M64.20)
Click 'Zoom in' for large parts diagram.
Diagram Ref No 9
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99310540942
The product you are viewing cross references to these numbers
- Porsche 993 (911) RS 1994-97

Fits:
Porsche 993 C2/C4 3.6L 1994-95
Porsche 993 Turbo 1995-98
911 (993) 3.6 L M64.05
911 (993) 3.6 L M64.06
911 (993) 3.6 L M64.07
911 (993) 3.6 L M64.08
911 (993) 3.6 L M64.60 TURBO
Inlet Valve. Valve Head Ø: 49 mm, Valve Stem Ø: 8 mm, Valve Shaft Length: 110 mm, Valve Seat Angle: 45 °
Click 'Zoom in' for large parts diagram.
Diagram Ref No 9.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99310540902
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) TURBO 1994-96
- Porsche 993 (911) TURBO S 1994-97

Valve Head Ø: 50 mm, Valve Stem Ø: 8 mm, Valve Shaft Length: 110,4 mm, Valve Seat Angle: 45 °.

Fits:
Porsche 993 C2/C4 3.6L 1996-98
M64.21
M64.22
M64.23
M64.24
Click 'Zoom in' for large parts diagram.
Diagram Ref No 9.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99310540502
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) C2S 1994-97
- Porsche 993 (911) C4S 1994-97