If not mistaken ms170 has open transfers like an ms250. The could be raised, widened with a dremel.
I was just cleaning my wife's ms170 and pulled the carb and compared it to a spare ms250 carb. The carb is nearly identical with the exception of the throttle linkage and of coarse the H and L adjustment. A brass plug on the front of the ms250 carb needs to be drilled out for proper impulse alignment.
I'm kinda Leary of modifying my wife's saw though. Lol. Anyway, glad you posted the port timing numbers*. Was always curious.