MTFCA Forum

I have two different styles of Champion X spark plugs. The style that appears to be of older vintage has the ceramic .285 below the face. The other is only .105. Would these be two different heat ranges?
Keith

There were all kinds of Champion 1/2" pipe thread plugs. Without pictures I don't think we can help much. Try googling Champion 1/2" plugs and you will see what I mean.

Are you referring to the size of the wire used to make the electrodes?
I don't think they really understood the effect of "heat range" of spark plugs that far back. That said, I am sure that the size of the wire would make some difference in the plug's heat range, however, I suspect the difference would mostly be negligible.
I have noticed the size difference in the electrodes of Champion Xs for many years. I never tried to figure how the timeline may have been involved. Used both larger and smaller ones. Never noticed any difference in running or fowling.

I believe what he is talking about is how much longer the exposed center electrode is on one plug compared to the other, and thus the difference in the height of the center porcelain below the end of the plug between the two plugs.

I am not even close to knowledgeable on spark plug theory, but due to some research on spark plug heat ranges in the last year or two I would SPECULATE that the heat ranges are different. I worked on a T that had a Z head and modern plugs. I had to put hotter plugs in it to make it reliable, not constantly cleaning the plugs. If I recall correctly the center porcelain was the main difference. Somebody more knowledgeable please correct me if I am wrong.

Terry

Yes Terry, That is my question. Is the plug with the ceramic.285 thousands down inside the base with more electrode exposed a different heat range than the one that the ceramic is only .105 thousands down and less electrode exposed?
Keith

Bump for help.

maybe this will help;
https://www.briskusa.com/spark_plug_cro ... ange_chart

The one on the left is a hotter plug, the right one allows the heat of the plug to bleed off into the head easier. The hotter the plug, the better suited it is for slow, laborous work as it burns off the carbon easier. Faster motors need cooler plugs.

Thanks Mark and Susanne.
Keith

If oil burning is not a problem i think it is a higher compression ratio that makes the need for colder plugs?? Bud. PS,There is a man in Indiana that sells spark plugs and has a cheap list that will show the many variations of Champ X. I can't find the list or remember his name?? Bud.