Stem angle...
 

Forgive my bad math...

If you go from an 82 degree stem to an 84 degree stem, for a 110mm stem length, how much height do you gain??

Approx. 2.5mm - waiting for confirm from group.

Need more information. What is the head tube angle, and do you have the stem in the up or down position (most important)? Also, do you plan to leave it the same (versus flipping one over and not the other)?

Without more info; I'd guess 3.8 MM -- or just over 1/8 of an inch.

about that much...
fingers held a little bit apart.

71.5 ha.

Currently have a Deda Newton 82 in 110, flipped down (so stem looks flatish). Wondering how much height I would gain going to an Oval brand 84 degree stem in the same length (flipped down), or a Deda Newton in 86 (flipped down)..
thx!

yeah, I get 3.8mm also w 84, 7.5mm w 86

Here's a link to a useful MS Excel stem calculator:

http://www.hammerheadbikes.com/docs/stemcalculator.xls

Actually, I wasn't trying to be a smart @$$.

I ran the numbers with 72, 73, and 74 degree head tube angles assuming you had the stem turn down as most people do and it didn't make a difference when results are rounded off.

If you had it turn up instead of down, then it would have made a difference -- but I guessed you didn't.

?? I didn't think you were being a smart ***. I know that if I flipped the stem, I would gain a lot of height, but I don't really like the look of a stem pointing waaay up. :) I was thinking of just going with an 84 instead of an 82. Even the 86 Newton I find points up quite a bit - especially noticeable visually when installed on a bike with a level top tube.

see also Habanero.com
 

they have a stem graph of drop versus reach that includes head angle.