[luckeyds]

I'm happy with what I have:

All aluminum Shelby 427 with a 428 Cobra Jet crank and aluminum Shelby heads: 550 hp and 600 lb-ft.

What I would do differently:

Port and polish the heads, a little more compression, and possibly use a billet 427 crank to turn a few more RPM; although it's quite a rocket already.

However, I run a 331 in my Mustang racecar and it's faster on the track.