Sn95 Head And Hesitation, Help Appreciated!

[g95fiveoh]

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.

 

[jrichker]

Identifying GT40 heads
Revised 26 may 2018 to include spark plug angle pictures and text descriptions.
The GT40X are aluminum. The GT40 & GT40P heads are iron. Use a magnet and it will stick to iron, it will not stick to aluminum.

GT40 heads have 3 bars cast into the front or rear sides of the heads.

GT40P heads have 4 bars cast into the front or rear sides of the heads.

GT40 heads have angled spark plugs, flow slightly less than GT40P. Stock and aftermarket headers fit with no problems
GT40P heads have flow slightly more than GT40. The straight spark plugs mean that some aftermarket headers don't fit properly and spark plug wiring may be very close to the headers and burn easily