Wayne & friends: After several hours of reading this thread, I'm encouraged and can't wait to try these mods on my GMS 47. My engine was new last year and was broken in on an SE last summer. This Spring I installed the GMS on a 4 Star 40 I had built as one of my winter projects. I have not had a single successful flight with the 4 Star. The engine tunes up great in the pits: good idle, smooth transition and great WOT, but it won't fly. The GMS quits in the air every time. The engine has all the symptoms mentioned in this thread. I'll keep you posted and I hope to be able to add another success story soon.