Thread: A few tips
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Old 02-23-2019, 09:40 PM   #17 (permalink)
ksa8907
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I didn't see the explanation here yet so I'll do what I can. The difference between a "hot" and "cold" spark plug is how far the plug reaches into the combustion chamber. Ideally you would always use a plug that puts the electrode at the center of the combustion chamber but that is not feasible or possible a lot of the time due to mechanical interference and (here is the hot/cold part) the further from the head the plug extends the more heat is retained which does and will contribute to knock/preignition/detonation.

High performance cars use colder plugs because they run higher compression, generate more heat (more power, duh?), thus need to use a plug that will dissipate heat into the head via the spark plug threads.

Unless you have modified your engine significantly, use the oem spec plug.

https://youtu.be/lS5XofKnros
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Last edited by ksa8907; 02-24-2019 at 02:37 AM.. Reason: Spelling
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