spark plug read....

[Tail_Gunner]

I have gone from ac43 to ac44 simply because the 43's would get pretty dark after a year or so...So i put in the 44's and after one tank of gas..40 gallon's the plug's are still pristine white...should i not have gotten some discoloration???

 

[Walt T]

The difference is the heat range. Can you post pictures of both plugs? The condition of the strap and electrodes tell you if the range is correct. Quite frankly if its running fine and not detonating you're probably okay. It is the ability to correctly "Read" spark plugs after they've been run a bit that determines the correct plug. Competition racing will find different plugs in different cylinders as crews try to get as much out of each cylinder as they can and run on the ragged edge of destruction.