You are going to get a tenure track position at a real academic program if you have shown the potential that you can do tenure worthy research and teaching. So, if you are at a mediocre university program, make sure that you position yourself for a fellowship at a top-notch institution. If you do neuro, consider doing a 2 year fellowship with a research year. If you do something else, talk to the places you interview at about the possibility of doing a research year. They might be willing to throw you a 1 year fellow, 1 year instructor deal. Also, document, document, document. Give grand-rounds presentations, teach the PA students, do anything you can stack in your CV as teaching activity.
If your program doesn't do any worthwhile research, resist the temptation to do tons of case reports and 'retrospective series' in 'imaging rag weekly'. Yes, it will lenghten your publication list, but if you are really looking for an academic career it tends to dilute your real achievements.
I assume you are either a first year or about to start in july. Consider setting up your own research program. Sometimes, there are opportunities to work with some of the basic science guys at your school without being dependent on the decrepit research infrastructure of your rads department. In the basic sciences, the saying goes that you can't achieve tenure until you have killed at least 1000 rats. The corollary for radiology is probably that killing 12 rats for a paper or growing a cooler full of cell-cultures is going to get you further than reporting on 'our experience' in implanting the newthingy PICC in patients with borderline immunosuppression. Also, the moment you do anything basic science + radiology, people will shower you with 'young investigator' money.
If you have what it takes to be a real academician (I don't), please don't let your suboptimal match result dissuade you from that path. Rads is doomed if we don't have motivated researchers in our field. You are not going to make 500 to a mil per year (or like one of our dumb_#$ 3rd years on SDN trumpets around 'easily 5 mil). But you will make a good living while doing something worthwhile.