Ok, I recently put autolite 104's in because I was getting a popping through the exhaust during exceleration. Well yesterday I pulled the # 3 plug looked great ( tan) pulled the #5 and it was really black. I checkthe plug wires and the #5 was crack and almost broke in half so I replace that and now I'm getting a really loud popping sound again It's all under exceleration. Could it be now that #5 is firing correctly that all the carbon on the plug is causing the popping? What does Valve float sound or feel like?

 

any one?