Got some test times last night, had trouble getting video uploaded, but will try again later.
Tested a stock 026 with 16 inch bar and chain and every rim I could get on it. Both chains basically new with 1 or 2 light sharpenings. rakers untouched. both chisel chain .325 Stihl RS and 3/8 carlton both 50 gauge. 4 test cuts for each combo 2 from each end of the log, took best time.
Wood was 13.5 inch poplar and 8 inch fir.
A few interesting things.
-In the poplar .325 7 and .325 8 were almost dead even
-Saw would even pull 3/8 8 or .325 9 in the bigger wood, just took a light touch.
-.325 8 and 3/8 7 were dead even in smaller wood, but 3/8 8 was faster.
Guess results will be different for everyone, but this is the second time I found pretty much the same thing.
To me it looks like a 50 cc saw is about the cut off point .325 to 3/8, that follows pretty much what the saw makers do as far as set up, seldom see a sub 50cc come with full 3/8 and don't often see anything over the 50-60cc range come with .325. If it can go either way with a 50cc 026 then I would think jumping up another 10 plus ccs would favor the 3/8 more.
I'l try to get some video up later.
Mountain, how high up are you cutting? Elevation makes a big difference, If your up several thousand feet into thin air your 60cc stock saw would only have the torque my 50cc saw would have down here in the lowlands. That could make a difference in gearing.