302 Swirl Port Heads ?

Read the Mopar Performance Engine book. He doesn't go into great deal about it, but Larry Shepard says that they found the early 70s heads were all swirl port heads. That means every one of them, because they are all about the same. I do remember he said they found it quite by accident. I've always thought that's why the small block heads were so good compared to everybody else's factory head. The chevy guys have to step up to a Bow Tie head to get better than a stock 360 head. And the Ford guys never even had anything that good until the GT40 and GT40P castings.