Oh, forgot. They also mentioned something about old "oval port" heads. My contact at Esslinger wasnt sure what year they were available on the Mustang, but he was under the impression that they were available in some of the early FOX cars. He had said that in their recent testing, these oval ports had been best for making power in an unported head condition. Anyone know anything about this head design and if it was availalbe on the Mustang???