Product Information
Valve Spring
Sold each
The Porsche Valve Spring is a critical component
of the valve train system fitted to numerous Porsche 911 and Porsche 964 models
from 1965 to 1994. Designed to maintain precise valve operation throughout the
engine's RPM range, the valve spring ensures that intake and exhaust valves
close correctly after being opened by the camshaft.
Fits:
- 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
Diagram Ref No 13
In Porsche's legendary air-cooled flat-six engines, accurate
valve control is essential for maintaining combustion efficiency, engine
performance, reliability, and long-term durability. The valve spring works
continuously under extreme mechanical stress, cycling thousands of times per
minute to keep the valve train operating correctly.
Whether you're rebuilding a classic Porsche engine,
restoring a 911, or carrying out a cylinder head overhaul, replacing worn valve
springs helps maintain factory performance and reduces the risk of costly
engine damage.
What Does the Valve Spring Do?
The valve spring is responsible for returning the intake and
exhaust valves to their closed position after each opening cycle generated by
the camshaft.
Its key functions include:
- Maintaining
correct valve timing operation
- Ensuring
valves close fully and consistently
- Keeping
the valve train under proper tension
- Preventing
valve float at higher engine speeds
- Supporting
engine compression and combustion efficiency
- Protecting
the valve train from instability and excessive wear
Without adequate spring tension, valves may not close
correctly, leading to poor performance and potential engine damage.
Why Does the Valve Spring Fail?
Valve springs are constantly subjected to compression, heat,
vibration, and high engine speeds. Over time, these factors can lead to
material fatigue and a gradual loss of spring tension.
Common causes of valve spring failure include:
- Metal
fatigue from repeated cycling
- High
mileage wear
- Prolonged
exposure to engine heat
- Over-revving
the engine
- Corrosion
or contamination
- Performance
modifications increasing valve train loads
- Age-related
weakening of spring material
- Improper
engine assembly or valve train geometry
As spring pressure decreases, valve control becomes less
precise, particularly at higher RPM.
Common Symptoms of Worn Valve Springs
A weakened or damaged valve spring may cause:
- Loss
of engine performance
- Valve
float at higher RPM
- Rough
idle
- Engine
misfires
- Increased
valve train noise
- Reduced
power output
Inconsistent
compression readings
- Premature
wear of valves, guides, and camshaft components
In severe cases, a broken valve spring can result in
valve-to-piston contact and major engine damage.
When Should You Replace Valve Springs?
Valve springs should be inspected whenever the cylinder
heads are removed and replaced if any signs of fatigue or wear are detected.
Replacement is strongly recommended:
- During
complete engine rebuilds
- During
cylinder head refurbishment
- On
high-mileage engines
- When
installing performance camshafts
- If
valve float is present
- When
spring tension falls below specification
- During
preventative maintenance on restoration projects
- Whenever
a spring shows signs of corrosion or damage
Many experienced Porsche engine builders replace all valve
springs during rebuilds to ensure consistent valve train performance and
long-term reliability.
Related reference numbersRelated, superseded, cross reference or alternative numbers for comparison.
90110590151The product you are viewing cross references to these numbers