If you burnt an exhaust valve from running LOP, it could only have been from being say 10dF LOP while at 1000' at 29" and 2700RPM......that would heat your heads up really well and eventually cause distortion, which leads to a valve problem.
Please tell me you did not do that?
The reason you had a valve problem, and my guess is this was a factory built jug from TCM, was the valve guides were inserted and not "post reamed" and the poor little valve never stood a chance at being square to the seat.
Too many myths perpetuated by people who know very little about the topic, but are qualified to work on your engine. More myths repeated over the years.
I used to run more than 10dF LOP, more like 50. Also, would never allow CHTs greater than 380F. That would save me about 15% on fuel bills, going about 10-15kts slower. Maybe it was just a badly fitted guide but it lasted 1300 hours so not sure about that. Whatever, my LAME quoted me some Lycoming document that said no way should I be doing that. (Yes, I know lots of LOP experts poo poo that doc.) And he gave me a good wrap on the knuckles for 'running too lean' and told me that fuel is the cheapest thing I will put into the plane! Having cylinders overhauled does knock a pretty big hole in the fuel savings. The engine does not run nearly as cleanly ROP. I'm resigned to that now and prefer the extra few ROP knots in any case
Sorry about the thread drift btw. But these are debates you get into with an analyzer.. Sometimes there are more questions than answers!
