Quote Originally Posted by tidefan66 View Post
So after doing some reading it seems that the early 90's Mustang GT 302 was rated at 225HP and the Cobra at 235HP. I was a little surprised since I thought they would be closer to 300. What would it take to get a late 80's/early 90's 302 up to 300HP? As I said earlier I plan to use the block assembly from the Mercury and swap heads and cam as well as going to a carburetor setup, probably a Performer RPM. If the GT40 heads have 65cc combustion chambers then couldn't I go with a small dome top piston to get the compression back up? The aluminum ones that Ford Racing sells claim to give you 65HP but those are pretty expensive.
If you are staying with iron heads, the GT40P have a 59cc chamber('97-'01 Explorer) and a much better flow rate even with a bit smaller exhaust valve. Plugs can be a bother to get out, needing proper head specific headers but many Mustangs are running these heads. You then, assuming you are staying with Ford parts, can install one of their 'letter' camshafts. Pedestal mount rockers should be changed out for stud mounts using the Crane mod kit or, better yet, have them machined for proper 3/8 or 7/16 inch studs. Find my current post here on my trials and pain with pedestal mount rockers. Then, a good ignition - either a DuraSpark or an MSD or similar. With that, should be near the 300Hp mark. Oh and the 1.7 rockers - today, installing my new Crane 1.6 stud mounts, have found signs of some minor interference on the retainers