i have run several 660 066 variants, theres nothing you cant do with a good 32 bar,good chain shaping tech, and a good woods port. i have run a 42 on a regular oiler running thicker oil and it will hold better and not fling off as bad but its just not enough. even the ho oiler is strugling if your really working the saw. just run your bar you got on it throw a dual port muffler and a good woods port and just smile as you throw chips. Even on my wild big bore dual port race ported 066 i only run a 28 cause even though i do big trees its not worth it to me to haul that heavy :censored:er up and down a mountain all day. i cut 4 footers almost weekly with a 28 just cause its light and you cant bog it out. Plus it pisses off all the old boys running there big bars and i still do more board foot a week then them with my 28 bar