what are the results if i bend my right arm past 90* at the top of my swing.

You kill your shoulder turn, you lose power, and open the door to inconsistency galore. That is a sign of an overturn, and chances are your weight does not have much of a chance to get off of its left side. Downswing will give you a little reverse pivot which spells trouble.

It all depends: if you have a one-plane swing (left arm and shoulder on substantially the same plane at the top), a lot of right elbow bend is fine and probably desirable; check out Hogan's and Trevino's swings.

In a two-plane swing (left arm distinctly steeper than the shoulders at the top), you need width and a bend of more than 90* could spell trouble: check out Davis Love.

Jeff