Thanks Charlie;
Although I'm building an RV-8 with a turbochgarged Mazda, I also have a Thorp T-18 with an O-290G, converted.
I have become VERY interested in Lycoming 4 cylinder enignes, but not in the $30,000 range for pre-assembeled engines. That leaves me cold.
Searching Part numbers and building up a low buck powerhouse is a lot more fun, and the end result is the same: good reliable power.