BB cylinder head question

The '67 915 castings are really the only true performance heads ever made for the big block engines, with the exception of some of the Max wedge stuff, like the 518s. All the others including the 906s everyone cherrishes were used on every thing under the sun from 440 Road Runners to 440 taxi cabs to 2 barrel 383s in grandmaw's station wagon. The 516s can be made to flow very similar numbers though if you use the larger exhaust valve. Those '67 castings were the only year Mopar installed the big valves in the 915s, and not all 915s that year had the big valves. Just the HIPO stuff. The 67 915 big valve castings outflow ALL other stock castings ever made by mopar with the exception of some of the Max Wedge stuff. That includes the 906s and all their derrivitives. the 346, and the 452. All three of those castiungs flow the same.....in fact, the 452s outflow the 906s......although by such a narrow margin, you'd never know it except on a flow bench or a dyno. Mopar Muscle magazine has a real nice article on the big block heads and highlights all these points in depth. They are indeed a quench head, as JohnRR pointed out. the flat area opposite the spark plug is where the squishin takes place. This is why they are such good heads.