Found an interesting formula on the net.
http://www.beyondtheboxscore.c...t-game-100-mph-swing
Basically the formula is:
coffitient*pitch Speed + (1+coeffitient)*batspeed at Impact.
the coeffitient for Wood bats is generally around 0.1 but can go up to 0.2 under perfect conditions. 0.1 would be a very well struck ball and 0.2 a perfectly struck ball with a really good Wood bat in heat
. So realistically you probably can say 0.15 is the best you can achieve in most cases (can also be much lower of course if you cut the ball).
So if we use a swing from the Tee and a batspeed of 80 mph it would be 80*(1+.15)= 92 mph
If the same swing is put on an 85 mph fastball it would be 92+0.15*85= 105 mph. this is the Maximum of course only if you really strike the ball well.
that also Shows that the "the faster it Comes the faster it goes" is not really right.
by that formula a 75 mph changeup will Exit at 103.2 and a 100 mph fastball will Exit at 107 mph.
of course technically the 100 mph goes faster but the difference is only 4 mph which is rather neglectable.
I don't really know the coeffitients for metal bats but in theory BBCOR should not perform much better than Wood if both hit the sweetspot (which is easy to do from the Tee but hard against a pitch).