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Related, superseded, cross reference or alternative numbers for comparison.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Related, superseded, cross reference or alternative numbers for comparison.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

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 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

6 per engine. Price is for each.

Fits:
Porsche 993 1994-98
Click 'Zoom in' for large parts diagram.
Diagram Ref no 2.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99310432172
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
6 per engine. Price is for each.

Fits:
Porsche 993 1994-98
Click 'Zoom in' for large parts diagram.
Diagram Ref no 2.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99310432172
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

6 per engine. Price is for each.

Fits:
Porsche 993 1994-98
Click 'Zoom in' for large parts diagram.
Diagram Ref no 3.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99310432271
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
6 per engine. Price is for each.

Fits:
Porsche 993 1994-98
Click 'Zoom in' for large parts diagram.
Diagram Ref no 3.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99310432271
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 established method of setting valve lash with a feeler gauge often provides for a "close enough" result and rarely provides for accurate, consistent, and easy to obtain precision. STOMSKI RACING's new version of an old-standby takes the "feel" out of setting valves and provides absolute precision, speed, ease of use, and consistency. By conveniently mounting a travel indicator over the adjuster of the rocker arm, STOMSKI RACING's 911 Valve Lash Adjuster allows you to quickly and accurately set and confirm the actual valve lash without settling for "close enough" or wondering whether your feel is consistent while trying to contort a feeler gauge into the far reaches of the 911 engine.
The SR097 is precision machined from 6061 aluminum and anodized for years of service on all 911 engines including 964s and 993s. Also available are a range of dial indicators including metric, digital, and compact travel indicators for use in restricted areas (pictured).
PLEASE NOTE: this tool does not come with the gauge
- Porsche 911 1965-1968 2.0L / 912 SWB (F)
- Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
- 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
- Porsche 911 1975-1977 3.0L Turbo (930)
- Porsche 911 1978-1989 3.3L Turbo (930)
- 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
Engine Valves, Valve Guides & Valve Springs – Precision, Performance & Reliability for Porsche Engines
The valves, guides, and springs form the heart of your Porsche’s cylinder head, precisely managing airflow and combustion efficiency. Intake (inlet) valves allow the correct air-fuel mixture into the combustion chamber, while exhaust valves release spent gases. Working together with guides and springs, they ensure perfect timing, compression, and power delivery.
At Design911, we offer a comprehensive range of precision-engineered inlet and exhaust valves, valve guides, and valve springs designed for performance, durability, and exact fitment across Porsche models. Each component is manufactured from heat-resistant, high-grade steel or titanium, ensuring reliable operation under extreme conditions.
Whether rebuilding a classic air-cooled flat-six or maintaining a modern turbocharged engine, our high-quality valve components deliver the precision, strength, and sealing performance your Porsche demands.
What Do Valves, Guides & Springs Do?
These components work in harmony to control the critical air and exhaust flow that determines your engine’s power, efficiency, and longevity.
Core Functions:
- Inlet
Valves: Regulate air-fuel intake into the combustion chamber.
- Exhaust
Valves: Release burnt gases efficiently during the exhaust stroke.
- Valve
Guides: Maintain valve alignment and prevent side wear.
- Valve Springs: Control valve movement, ensuring precise timing and closing pressure.
Together, they keep your Porsche engine breathing freely, running smoothly, and performing as designed — lap after lap, mile after mile.
Why Do Valves, Guides & Springs Fail?
Valves and related components endure extreme heat, pressure, and friction. Over time, these conditions can lead to wear, deformation, or loss of tension, affecting airflow, compression, and overall engine performance.
Common Causes of Failure Include:
- Valve
seat wear or pitting, leading to compression loss.
- Burnt
or bent valves caused by overheating or timing issues.
- Worn
valve guides, increasing oil consumption and exhaust smoke.
- Weak
or fatigued valve springs, resulting in valve float at high RPMs.
- Corrosion and carbon build-up from poor fuel quality or short trips.
When these issues develop, symptoms may include misfires, poor performance, oil burning, or rough idling — clear indicators that replacement or overhaul is required.
Why Replace with Precision-Engineered Valve Components?
Replacing worn valves, guides, and springs ensures your Porsche engine maintains proper compression, valve timing, and airflow — all essential to reliable power delivery and fuel efficiency.
Key Benefits:
- Restores correct airflow and combustion efficiency.
- Improves engine compression and throttle response.
- Prevents oil leakage and smoke caused by worn guides.
- Eliminates valve float and restores high-RPM stability.
- Crafted
from premium heat-resistant alloys for durability and longevity.
- Perfect fitment across classic and modern Porsche engines.
Precision-engineered components bring your engine back to its optimal condition, preserving both performance and refinement.
Highlights:
- Comprehensive range of inlet and exhaust valves, valve guides, and springs.
- Precision-manufactured from high-tensile, heat-treated materials.
- Restores compression, power, and valve timing accuracy.
- Improves reliability and reduces wear in high-performance engines.
- Designed for rebuilds, restorations, and performance upgrades.
- Compatible with air-cooled and water-cooled Porsche models.