My 422 smallblock build
The reality of a head having that much pressure drop (28) is —- and correct me if I’m wrong but I don’t think so—— ) impossible.
A head flowed @10 is much more reasonably accurate or closer to real world operations. The world is just used to the rags flowing everything at 28. And then we base our understandings in that.
@SSG_Karg , lifting the valve passed peak, even more so since your flow rates don’t tank, allows the valve more time (coupled with duration) at the max flow area allowing more air and fuel into the cylinder.
If you stop lifting the valve at max lift, it spends a very short time there and flow decreases rapidly. This is also why a roller is better. The cam lifts the game up, let’s it sit there, then brings it down. With a roller, when making big power, the larger the cam is, the better it makes power with hanging the valve open longer.