When it did fire it went with a bang not a normal firing. I got home from work today and decided to pull the cylinder off before dinner and I found that one of the piston rings was broken. The cylinder has a small score too. So now I have to get it all fixed before race day this weekend. Lucky I have a couple of spare engines to rob. Still after fixing helicopters all day I dont feel like spending my evenings getting greasy again. However its worth it when you manage to smoke all those 4 strokers on the track.