There was another game at Illinois with Marble, Armstrong. Horton et. al that was quite a comeback.
1/14/1987. I remember watching it. Down 22 I believe with roughly 17 minutes left, something like 60-38. Won in OT also if my memory is correct, 91-88. I honestly believe it was the greatest comeback win I've ever seen by Iowa from a points and quality of opponent standpoint.
For some reason I think there was a larger one some time in the last 15 or so years in a non-con at home where we were down 23 very early, then smoked them. One of those southern small type schools like Grambling.