The 790/SP/PM105 series with over 13 years of production (1964-1977) probably cut as much timber as most other 6 cube makes put together. There was also a bunch with the 99cc motors 1-76/740. Plenty of McCulloch two man saws used the same 6 cube motors.
Everyone needs atleast one 6 cube chainsaw.
How about the McCulloch 550 and Super 550 saws (99 and 103cc IIRC)? How did they compare with the the McCulloch 790/795 saws (or with the Homelite XP1000/1020/1050 and Homelite 650 saws for that matter)?
I know I was real impressed with my friend's Homelite Super 650. Had more rpms but a smidge less bottom end than the XP1000-1050 saws. He has a Super 650 that was 'enhanced' a bit for racing years ago. Unfortunately, it got crunched, and has been sitting sadly on the shelf for years. I believe it's salvageable. Need to light a fire under him to get it back in shape.....
The old homelite 5.8ci/95cc DD saws are pretty healthy too. 700D, etc. The Homelite gear drives of that engine size aren't fast, but are quite strong and will pull a big bar wrapped with big chain. Super Wiz 77, 770G, etc. Then there's the 1100G and 1130G saws if we're talking six cube gear drives.