Originally Posted by
bcchi
Yes and I wunder what the difference is between the OS 15 Gas and spark and the OS 15 GG.Compression porting ? Your fuel mix is what we used years ago in four stroker converted to spark.Spent a couple of winters in Benson AZ
I flew at sierra Vista.
BCCHI
Not sure about the head / compression differences but OS parts lists the same cylinder liner for the GGT 15, the ignition 15 and the glo 91FX.