tychoc,

I didn't know about the muffler problems. Interesting. I have had both come loose in flight one time each, but I tightened both down well and didn't have the problem again. I did have to use hi-temp thread locking Permatex on the long bolt that holds the muffler halves together. That is a problem if you don't tightenen them down enough. After talking with W8YE, I'll be getting the Tower mufflers on my next order for both Evos.

The thing that I like about both of mine is the wide, forgiving tuning range for the hi and low speed needle valves. I can be out of tune and the engines still fly well until I tweak them a little. The .45 training engine is the most forgiving and almost never needs tuning.