contract and devt

solely bought a car, but friend's name on title since I didn't have insurance at time of purchase. friend signed informal contract stating he owed me 1600$ and that "the car was soley mine". Friend will not sign power of attorney to give me sole rights to the car. do i have a case with the contract

I can’t say if it is a good contract without seeing it, but you do have a case if the contract properly worded.