I had a SHM stoker in my Mach when I got it. I sold the shortblock because it had what I believed to be a sticky ring or something that effected the compression in at least one hole - but it wasn't consistent. Only a few times while I had that motor did it seem to run to it's potential but most of the time it seemed down on power. I have to be honest, I didn't see anything wrong with it when I pulled it apart and the guy who bought it said that he didn't think there was anything wrong with it at all - so who knows.

Just thought I would toss that in there.