My friend is in need of a cam for his 87 GN and his girlfiend wants to buy it for him for Christmas. Need help deciding which one because I don't know much about turbo Buicks. What I know about the car is it has champion ironheads, yellow top injectors (not sure size), 63 precision turbo, and has a stall but don't know the size. I know it needs to be a hydraulic. Would appreciate any help. Thanks