cracked magnum heads
I found that there are some based on a particular casting number, those are the reinforced version and have stock size ports.
As for the others, jegs and speed master..etc..which are 179cc intake port...
179cc is about 24cc larger than a factory 2.02 915 J head@155 and 160cc w/1.88 fwiw and based on heads I have and measured.
I would think they would have to be pretty messed up to not flow more.
Also...
Hughes says "easily" and "inexpensive"
Does not say can't or will not.
They are saying they've decided they want more money, and what an opportune basis for doing so..."they changed the heads on us , uh... so... $$$$
Still, just my opinion.