Help needed for backfire ? issue

Todays update. Took the boat out and again ran w zero issues. I will mention that there is the slight shudder after running hard and then coming back into the no wake zone. This is the shutter I had mentioned in another post. Could be the motor isn’t balanced 100% internally, could be a number of things, most of which I am clueless about. For now I am focusing on the current backfire popping. None of that today. She ran fast and strong. I did notice some smoke at initial startup though. I made a point of feeling the coil once back at the dock. I don’t have an IR thermometer. All I can say is it was very hot. I could basically put my hand on the valve covers and the exhaust manifolds. I could not keep it on the coil, way too hot. Is this normal or indication that the coil is running too hot. Should I order the coil mentioned above from Rock Auto? Thank you