Generally, programs with money are more flexible. Basically, the department is sacrificing clinical income for several yrs while you're on your K08 or doing 60/40 time in the lab or whatever.
Part of it is based on the chairman's attitude and what he/she wants for the department. Is he/she a scientist himself/herself? Do they have a history of mentoring people who have gone on to research based academic careers? My program, WashU, has an awesome chairman who wants scientists in the department and mentors them. We have 4 or 5 people on K08's now who will be going for R01's. Another full-time faculty member is going for an R01 too. The chair's support means a lot.
Departments with established strong research programs definitely fit your bill. These are places like JHU, Iowa, MEEI, Michigan, WashU, Pitt, UDub etc. But any program with good research will probably also be very supportive - Oregon, Ohio State, UCLA, Baylor, Penn, UNC come to mind. There are many others.
There aren't that many ENT's with R01's, period. Try to find where those people trained. Also, understand that it is extremely difficult to be a hardcore researcher and a full-time clinician. It's taxing to you and your family. Many times you have to give up significant clinical time. This translates into weaker clinical skills. You have to compromise somewhere to make time for your research career.
Good luck.
