Hello Eric,
Don't know much about tanaka's but have had 2 olympak 999f models. thats the 6 cubic inch model. very well built saw. I modified a few and they ran very strong. they came with the larger tillotson ht-1 carb and had big open loop transfers didn't have to change to much to really make them run. but never could get them to outcut the 2100 and 394 husky's