Spark Plugs
Chapter 2
Study Tips
The spark plugs are critical parts that dominate
the engine combustion and bear a major
responsibility for higher engine performance.
Spark Plugs
Chapter 2 Spark Plugs
17
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The center electrode uses the
world's first ultra-fine 0.4-mm diameter
iridium alloy for high performance and
a platinum tip is used for the ground
electrode to secure service life equal
to platinum spark plugs.
Ground electrode with platinum tip
Ultra-fine 0.4-mm diameter iridium
alloy center electrode
All-round laser welding
Housing plated with highly
corrosion-resistant, lustrous nickel
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The electrodes have been taken to the limit of fineness, so the contact area with the flame core is small, the quenching effect is
reduced, and the ignition performance is improved.
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can replace almost all normal spark plugs in Japan and overseas. When replacing normal spark plugs with
check in the application table.
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For normal engines, replace with the same heat range as the spark plugs being replaced; for a tuned engine, select spark plugs that
match the tuning level.
Sparks
Sparks discharge on the part
of the electrode where they
can spark most easily.
Formation of the flame core
The spark energy activates
part of the air-fuel mixture and
a small flame is produced.
Growth of the flame core
The flame grows even though
energy is absorbed in the
center and ground electrodes.
Ignition
Growth of the live coal
accelerates and finally, the
flame spreads as explosive
combustion.
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