Stealth heads with the seats recut and a nice bowl blend with flow right about 280@.600 lift.
Most home ported stock heads(especially 906’s and 915’s) I’ve tested are typically in the 250 and less range.
The 280@.600 is a little more than these flowed:
View attachment 1715901405
View attachment 1715901406
On my bench an ootb TF240 flows right about 316/221@.600, and 320/225@.700 lift.
I’ve tested about a dozen of them, they’ve all been within a few cfm.