If 'new pipe' means replacing the stock pipe, that's a 'for sure!'.
The pipe choice for the 220 gets a bit iffy, seems to me (from what I've read anyway).
The 220 is generally agreed to have a good bit more bottom end than the 200, but is lacking considerably on the top end of things. Depending on whose opinion or whose ad you read you will get a considerably different idea of what pipe fits your needs for a 220. Heck, FmF even gets the profile names screwed up between the two KDXs. At times they have even stamped the different pipes with the wrong ID.
The choice of most 220 owners is the -30 (rev or 'desert') pipe. The effective power band of that pipe is considerably higher than the -35 (torque or 'woods') pipe.
Avoid the use of adjectives to define the pipe profile. A good number of riders have no clue what they are talking about when it comes to pipes. Saying, 'I have an FmF Gnarly pipe' doesn't mean anything when it comes to
what profile is being used.
The -35 is smaller at the bell (where the con/diverging cones meet) than is the -30. Eleven and fourteen inches respectively if I recall correctly. If you need to know for sure, ask..I'll measure them again.
If you want more on the stump-pulling power end of things, the -35 is the choice for the 220. It's still going to be flat on top..really flat with the 33mm carb.
You should have plenty of bottom end to go around with a -30 on your 220. That will also give you more grin on the top end of things, too!
My 2-hunny with a -30 has all the bottom end you could ask for. I don't know
why you would need a -35 on the 220.
Lots of grunt! I'm not saying no one uses that pipe on a 220. Skipro does and likes it just fine!
The two pipes are considerably different is all. If you can swing it, buy 'em both and choose based on the seat of your own pants!
BTW...the -35 jets considerably more lean (-2 main) than the -30 does. Well...on my 200..according to me, anyway!
Consider sending in the cylinder head with the carb, especially if you ride at any elevation to speak of. Ron will reconfigure it...not so much from the added static compression point of view (although that, too) as a reconfigured squish band.
As long as you're not riding it...might as well kill two birds with one stone.
Be sure to tell Ron your elevation...and what fuel you are going to be using.