I know this has been covered a thousand times, my apologies in advance. google_ad_height = 600; Special thanks to: “Thank you, for the info, on your site, on how to remove valve springs, and install stem seals, using normal shop tools. Use a colder heat range for leaner air/fuel mixtures. Because they have a longer insulator nose length, heat is transferred from the firing tip to the cooling system at slower pace. jetting !!! Want to know more about your particular Make and Model vehicle? You sometimes see a very bright white electrode with black dots on it also as a heat range issue in some cases cracked electrodes. //--> Shop the latest Engine Builder merchandise. being transferred more readily because the of the relatively insulating/cooler rings, to be fused to the white porcelain as tiny black specks, also fused However, it does not impact its heat range. Normal. With the early signs of detonation, the shock-wave Replace with a colder heat range of Autolite spark plug. google_ad_client = "ca-pub-4230976174889513"; 343