Originally posted by Rev. Po-Jay:
The colder you go the more easily motor damage can happen. The way I understand it is that the plugs act like a fuse. Hotter plugs burn out easier. Plug burns out the piston does not.


That makes no sense...

A colder plug resists detonation better because it retains less heat.

For choosing a plug's heat range you want to run as cold a plug as possible without causing it to foul out because it's not hot enough to self clean.

A plug's heat range is basically it's ability to transfer heat to the cylinder head and it's water jackets. Therefore a colder plug transfers more heat and as a result has lower cylinder & plug temps. (I.E. ideal for high CR or Forced Induction)

2000 SVT #674 13.47 @ 102 - All Motor! It was not broke; Yet I fixed it anyway.