If you have a stock torque converter, I wouldn't go any bigger on the cam than what you have. If it were me, i would put in about a 3500 stall and a 750 DP and worry about a cam later. Do you have a Performer or Performer RPM? If just a regular Performer, A swap to an RPM or a Holley Street Dominator would be an improvement. IMO , the biggest gains will come from a carb and coverter change.