After an hour flight doing touch and goes, and flying around the Blue Ridge Mountains on a beautiful severe clear day the story begins. I was on my way south descending into my home airport pattern when the EGT and CHT on cylinder #1 slowly progressed downward to zero, followed by a rough engine, and an intensified "close in final", and ironically the best of the six landings for the day. Taxiing in, the #1 remained cold until shutdown. Oh well, exhaust valve? Mag? Induction? A friend and I