Which saws share nearly identical components?

[litefoot]

I was curious which saws series share roughly similar components but differ mostly in jug/piston. Examples would be (and correct me if I'm wrong):

Stihl 170, 180
Stihl 210, 230, 250
Stihl 034, 036
Stihl 270, 280
Stihl 240, ,260
Stihl 290, 310, ,390 (does the 390 fit in here)
Stihl 440, 460 (?)
Dolmar 6400, 7300, 7900

I know there's a lot more in other brands.

 

[GASoline71]

All the current line Husqvarnas and Jonsereds...

Gary

 

[hoss]

051/075, 070/090, homie 540/8800 solo 681/dolmar 7900(looks like) husky 2100/2101.

 

[Jacob J.]

That question stretches back as far as saws have been made and encompasses hundreds of models...