I have a 1995 5.0 Mustang. The last owner put an e303 cam in it, a CAI, a new distributor and wires. How do I tell what heads are in it? They are not aluminum or anything special, but how do I tell if they are gt40 etc. heads without taking anything apart? Also I found out that the car was only running on 7 cylinders for who knows how long. I went to check the spark plugs and one wire was not even plugged on, and the boot was burnt up. After fixing this, the car runs better but it hesitates when accelerating. It's like a mild jerking and it hesitates. Any suggestions? Could it be iac? Timing? Injectors? This is my first 302.