Pro killer,
I think they flow better than what you are saying. Where did you get the info?
Here is a link to a head compare....it is with the older 171cc intake ports not the new 180's. They flowed 202cfm on the intake. The new 180's would flow better.
That's on a different motor. I'm saving up for a dart based stroker...but til then I'm running my 302 on those heads (ported), a blower cam (but pretty good n/a), and my cobra intake with a port and polish.
Got the heads for free so I figured I might as well use them.
I looked at the faq in the tech section...but those numbers just don't seem right. I've seen other sources that say different....maybe I should just call World products lol.