Specifications
What about electrode shape? Spark plug manufacturers will tell you that a small diameter center
electrode makes it easier for the spark to jump the electrode gap. This is true, but what they are
not saying is that such a spark is also weaker, since it takes a lower voltage to jump the gap. A
spark jumps the electrode gap when the voltage at the electrodes reaches the ionization point.
Since the ionization point (voltage needed to jump the gap) is lower when a small diameter center
electrode is utilized, spark voltage is also lower. Exactly what a performance-oriented consumer
doesnt want. Also, a spark that tries to squeeze itself through a small diameter center electrode is
slowed down and stretched out and, therefore, weakened even more. And finally, the electrical
energy carrying ability is reduced when the electrode diameter is smaller. Small diameter or
uniquely shaped electrodes could be beneficial if the ignition system is weak, but modern ignition
systems are all powerful enough to supply the voltage needed to create a spark across the
electrode gap of a conventional electrode design, even in high compression engines.
Silverstone
was especially designed for the increased demands of modern high performance
engines and is the only spark plug that optimally incorporates all desirable properties. The most
important decision when building spark plugs is what materials to use. Not the electrode shape.
The more than 80-year-old original design is still the most successful and widely used. Silver is
the best electrical and thermal conductor of any metal and, therefore, the best material for the
center electrode. In managing the ever changing combustion chamber temperatures caused by
different engine and load conditions, silver is unsurpassed. To prevent plug fouling, optimum
operating temperature is reached shortly after start-up; yet under full throttle when things really
start to get hot, heat is dissipated rapidly. Silver provides the widest heatrange latitude. As the
best electrical conductor, silver assures that the spark encounters the least resistance and no spark
energy is lost. Unlike conventional electrode materials, silver delivers even the most powerful
spark without any energy loss and therefore guarantees combustion initiation. The solid silver,
large diameter center electrode in Silverstone
increases spark carrying ability and with it spark
power up to 137%. Silver is extremely resistant to erosion, guaranteeing a virtually unchanged
electrode gap for the life of the spark plug. This greatly extends change intervals.
Silverstone
non-resistor spark plugs are guaranteed to be without internal resistance, making
them first choice for the performance-oriented consumer. Silverstone
is the most efficient,
durable and thermally adaptable spark plug available. Unlike other high performance spark plugs,
Silverstone
is technologically unrestricted to any one application. Silver spark plugs outperform
all other spark plugs and deliver the
most powerful spark.
Material Thermal Electrical
Conductivity Conductivity
W/(m·K) MS/m
Silver 407 66
Copper 384 57
Gold 310 45
Iridium 147 18
Platinum 70 10
Nickel 59 10
Properties of Materials
© 2004 Nology Engineering, Inc
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