Great experience with the NGK BKR5E-11 or BKR6E-11 (difference being the heat range). This is a V-grove plug, I've attached the spec sheet for both the plugs as well as the NGK plug naming chart.

Oh, in my case, I went from the hotter to the colder plug as I moved from a 9.5:1 to 10.5:1 static CR on my 360 motor.

NGK - BKR5E-116953 V-Power Plug.jpgNGK - BKR6E-11 2756 V-Power Plug.jpgNGK - SparkPlug Numbering System - 1.gif
Last edited by Diplomat360; 04/22/20 09:56 AM.