Lycoming's Thoughts on Using EGT for Leaning
 

I ran across this article that I thought would be of interest to many builders using Lycomings or clones.
So here it is:

http://www.geocities.com/sf260d/article/exhaust.html

Great info on Engine leaning and monitoring
 

Here are two very good references. They are published from two companies that make engine monitor, but they have great insight and info on indications (CHT/EGT/FF/OT) mean for normal and non-normal conditions in a Lycoming engine:

"Leaning and diagnosing engine problems" by Electronics international. It starts with a detailed explanation of how the engine works. This is a fantastic source of info and understanding of engine operation:

Leaning and diagnosing engine problems


"JP-700 pilot guide" - Good info of what differnt parameters can mean (section 3 - Interpreting data)

Electronics International JP-700 engine monitor Pilot guide


Cheers George