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Plug Heat Range

1171 Views 3 Replies 4 Participants Last post by  dfree383
Does going from one heat range to the next like autolite 3923's to 3924's make much of a differance, or should I jump 2 ranges to see if there is an improvement or not.
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I went from 3922's to 3924's and my engine seems to idle better and run a little stronger.
If you think about plugs, the heat range indicator is the distance the tongue and probe hang down into the combustion chamber, the hotter the plug the farther into the chamber, the higher chance of pre-ignition issues.
Just thought you should be aware.

With a hot plug, the tongue is deeper into the fireing process and will often become very hot (loosing it's heat transfer to the head from the excessive insulation or distance from it) and pre ignite the fuel mixture, and under hard running that cas happen as soon as the compression begins in extreem circumstances, and you don't want that to happen.

Generaly higher the compression the colder the plug.
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