Not much of a question since Michigan and Ohio State dominated the Big Ten for many years. Michigan State had a few years in the 60s under Duffy Daugherty, and Jack Mollenkopf at Purdue had 3 in the late 60s. Schools like Northwestern, Illinois, and Minnesota you have to go clear back to the 50s and 40s to find coaches that did it. Barry Alvarez only had 3 at Wisconsin as well as Bret Bielema, Indiana has only had 2 top 10 finishes in their history and has only finished ranked 5 times.
So my answer is zero. But I am interested in knowing where you are going with this. I think it is great that KF has led Iowa to 4 top 10 finishes, a couple of those years had Iowa in NC conversations. But the last time Iowa gave someone a pass because of how well he did in the past as a football coach set Iowa so far back that it took 19 years to have another winning season, Forest Evashevski. If KF runs this program into the ground I don't think you keep him as coach because of something he did in the past.