http://www.mototuneusa.com/break_in_secrets.htm
This seems harsh. However, this is the approach that I used for my track WRX. I did the first 30km on the street (up to 10psi boost, 1/2 and then full throttle, up to about 5500 revs) and then changed the oil. Did the balance of the run in on the track (12psi boost, full throttle, 6500rpm limit), followed by another oil change. I used mineral oil for the run-in plus two more events, then synthetic (Penrite 25/60). The engine is strong and the rings have bedded-in nicely.