Oh man, unfortunately that's becoming way to common, at work I've gotten valves, springs, and other parts, wrong parts correct box. It's pretty annoying.
Boy, I really wish I would have went with tf 270s.
It's basically what a standard port should be for anything over 471 cubes up to 512 in my opinion.
Or any race motor that can rev enough to use them! I think of the 270 on a 440 as similar ro a 240 on a 383,,,,,,,, or a max wedge head on a 426,,,,,,,,,