Oval ports are very limited on power potential without nitrous or forced induction,esp in app's that turn low rpm's like our trucks.

 

That's true too. However, that is what the Vortec intake manifold has. I believe the Ram Jet 502 manifold even has oval ports. The only option for a square port would be a custom intake manifold. When I end up turboing my Vortec 454 I'm thinking that I'm going to go with some Canfield square port heads and a sheet metal intake manifold.