AC 2 Spark plugs ?????

[Black Car]

Are AC 2 spark plugs rapid fire kind or what???
Has anyone used them???
What results??

TIA,
Gary

 

[gofstbuick]

I use to use the number 2 until Bruce (WE4) told me the number 1 is a little colder plug. So I switched to a number 1 rapid fire plug. It works fine for me. My engine seems to idle smoother. I really didn't notice a gas mileage increase.