I need to set equal height on a series of divs inside another div wrapper. The problem is that I dont want the same height on all of them. The page kind of have 3 columns an
Since you are using jQuery, are you using the EqualHeights plugin?
http://www.cssnewbie.com/example/equal-heights/plugin.html
Seems like you would have some logic to know how many divs are in a row before hitting the page width, then starting a new div row with a ID. Then call
$('#custom-id').equalheights();
as many times as you need to, and that should set them all to the same height per ID.
You could build on that too by doing an each for divs in a row, and adding their width with .width().