250's cfm is not the ceiling for those heads.
The oddball late 70's smog heads i did for randall do mid/high 260's cfm, like 266-268. The exhaust ,the better head of the 2, does about 200, the other 180's... and those aren't special castings with offset pr's and awesome exh ports. Just truck/van heads w core shift.
So..yeah, most could get more from them.
Again, cuz you're asking..they aren't bad n they aren't great or anything to get excited about.
In perspective, they were hi tech for 1975 when that part number came about.
