When my old engine was nearing overhaul, I decided to purchase a new engine for my RV8. I looked at several shops for the new engine, and settled upon the Lycoming-built Thunderbolt parallel valve YIO 360 EXP 271 (basically an IO 360 M1B). I liked the idea of having an American company build the engine, and the idea of having everything new. Jeff Shans, the Lycoming representative, was most patient with all of my detail requests for the new engine, including running the engine at full throttle on the engine stand for an additional 4.25 hours as it is difficult to properly break in an engine at our field elevation of 7600'. I now have 37 hours on the new engine; it is incredibly smooth for a 4-cylinder because of the excellent balancing that was done by Zach and Paul, the Lycoming engine builders who built my engine. It also is 5-8 knots faster than the old engine due to the porting and polishing and 10:1 pistons. In short, I am thrilled to have the Thunderbolt engine on my RV8. Thank you, Lycoming.