Raceral,
Well, those ports worked well enough to win Le Mans in '67 and the Nascar manufactuers championship in '68 and '69...
The 427 tunnel port is the ultimate FE wedge head design.
Those are not valve guides in the ports, they are pushrod tubes that allow the pushrods to go directly through the port. The other FE heads have a "dogleg" in the port to go around the pushrod that restricts flow. When I flow test TP heads I have a port extension that has a removable simulated pushrod tube in it to simulate the part of the head that is attached to the manifold on an FE head. There is less that a 5% drop in flow with the pushrod tube installed compared to flow #s with the tube removed. Ford figured this out in the '60s. The air and fuel mixture
does not go down the center of the port, it tends to stay along the port walls. This is why port shape, and not nessessarily port size, is so important.
Excaliber,
You might be thinking of the 302 tunnel port engine that Ford developed for the '68 Trans-Am series. The heads were too big to work well on a 302ci engine below 5000 rpm and only made real power from 8000 rpm and up. Unfortunately the bottom end of the engines had a hard time handling the PRMs and failures were common. In '69 the Boss 302 went in to production and bcame a potent winning combination
--Mike