Spark Plugs (Hot or Cold) W221.071 S500 UK Spec
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From: Karachi, Pakistan
W221-S500-2006, W123-250-1978, W126-500-1983
Spark Plugs (Hot or Cold) W221.071 S500 UK Spec
Once again, I have gone back to the books to revive my memory about spark plugs.
As I understand, Hot Plugs ie ones with numbers 7 onwards or so run hotter, thus better suited for regions where climate is cold year round e.g. northern Europe, Moscow, Siberia, Canada etc, so that the Combustion Chamber gets hot quickly and remains hotter.
Conversely a 'Cold Plug' designated by its number 5 etc would run cooler thus more well suited to all year round warmer climates.
Can anyone please comment to confirm or rectify my understanding.
As I understand, Hot Plugs ie ones with numbers 7 onwards or so run hotter, thus better suited for regions where climate is cold year round e.g. northern Europe, Moscow, Siberia, Canada etc, so that the Combustion Chamber gets hot quickly and remains hotter.
Conversely a 'Cold Plug' designated by its number 5 etc would run cooler thus more well suited to all year round warmer climates.
Can anyone please comment to confirm or rectify my understanding.
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S500
plug temp has nothing to do with the ambient conditions - and the heat range can vary between manufacturers - with champion and ngk the exact opposite
plug temp is about the state of tune and the emissions - run cool enough they don't clog - unless you have turbos run funny fuel and have wound boost to death just buy stock plugs or iridium if you want an imperceptible benefit
plug temp is about the state of tune and the emissions - run cool enough they don't clog - unless you have turbos run funny fuel and have wound boost to death just buy stock plugs or iridium if you want an imperceptible benefit
Thread Starter
Junior Member
Joined: Jan 2018
Posts: 49
Likes: 0
From: Karachi, Pakistan
W221-S500-2006, W123-250-1978, W126-500-1983
plug temp has nothing to do with the ambient conditions - and the heat range can vary between manufacturers - with champion and ngk the exact opposite
plug temp is about the state of tune and the emissions - run cool enough they don't clog - unless you have turbos run funny fuel and have wound boost to death just buy stock plugs or iridium if you want an imperceptible benefit
plug temp is about the state of tune and the emissions - run cool enough they don't clog - unless you have turbos run funny fuel and have wound boost to death just buy stock plugs or iridium if you want an imperceptible benefit
MBWorld Fanatic!
Joined: Aug 2014
Posts: 5,316
Likes: 1,673
S500
a given engine in a given state of tune needs plugs that run cool enough for the plug to survive (not cracking insulator or erosion)
and hot enough to burn off any despots that might build up and eventually impact ability to produce the spark
on a stock engine running stock fuel, used in typical conditions always use the manu recco plugs
and hot enough to burn off any despots that might build up and eventually impact ability to produce the spark
on a stock engine running stock fuel, used in typical conditions always use the manu recco plugs
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