That's a good research question, you are running 21's so you can definitely run 15" rotors and your choice of Brakes. If you run 12 or 8 pots on the front and 8 or 6 pots on the rear respectively with 15" rotors front and rear you can have a pretty amazing system. If possible I'd find the biggest rotors you can to fill up those wheels. Do you have a budget?
If you are selling your ride scratch the above.....
If you are selling your ride scratch the above.....






