ORIGINAL: kcc
If memory serves me correctly (and I may be wrong...), I think the G in GMS was Jim Goad, who ran Indy R/Cthey were the original US outlet for that engine. May have been an early attempt at a private label engine, as they were always made in China. The M and S were the names of two of his partners/associates in Asia. I know this may be off topic, but one of the comments above mentioned an ugly engineI'm not trying to start a fight, but we always spelled ugly engine/carb F-O-X.......
The older engines other than a few exceptions such as the Hawk were ugly, mostly because of their finish. But look at these and tell me if they are ugly to you?