Jim,
Why not keep the car as close to original as possible? If you are just gonna cruise and once in a while track time you don't need the Dart or forged crank and rods.
Jim Harrell (sp) has a 350 hp 302 in his Shelby FIA car and the thing just kicks butt. Probably has a lot to do with driver skill but a 302 nontheless.
Now if you want to do serious track time and almost no street driving you can go with the Dart 302 or 351 with higher compression, wild cam ,Forged everything and be making 500+ with the 302 and 600+ with the 351.
In my ten years of open track I have blown up a 427 Side oiler and a 351 Crate engine both do to poor oiling and weak bottom ends. That is why I chose to go with the Dart Block this time. Got to start with a good foundation but you being a builder you know all about foundations.
I don't like to make any recomendations regarding heads or cam because I am not an engine builder. Once you choose someone to build your engine tell them what you want the engine to do and let them pick the right pieces.
I suggest you pick a builder who will Dyno your engine and break it in before you install in your new Cobra.
Good luck,
Cranky
