The technical analysis paper that started Chrysler engineers interest:

https://digital.library.unt.edu/ark:/67531/metadc54614/

A few Hemi shaped cylinder heads had been built previously,
inspired by the ideas that a hemisphere has less metal surface for heat to leak out of,
or the valves can be bigger:

https://en.wikipedia.org/wiki/Hemispherical_combustion_chamber

“Cross flow, canted valve”
turned out to be where the “goodness” lay
rather than the hemisphere.

I admire all the Mopar Hemi’s
because each represents progress.

The Nissan NAPS-Z tweaks to the Hemi deserve respect,
as Bob Lutz acknowledges.

Bob Lutz lured away two brothers who worked at GM who were frustrated with their bosses who would not let them design a cross flow canted valve cylinder head with squish and tumble concepts to promote faster burn which enabled less degrees of ignition advance. Less degrees of ignition advance mean less “negative work.”

If a cheap way to make hydrogen is developed
expect the cross flow, canted valve, engine cylinder head will be further developed.

Its neat that the Hemi was a race engine first that was eventually and successfully adapted to a passenger car. All other engines were passenger car engines but used in racing. Fords attempt at this with their SOHC 427 just didn't work in its as offered state. The Ford 351 Cleveland 4BBL closed chamber heads I believe were race heads that soon after were adapted to passenger car use.

Wonder how history would have turned out if the ball stud hemi ever made it to production?

I find this more interesting as time goes on. So I have learned, The Hemi head was superior on the dragstrip and oval but EXPENSIVE impractical overkill for a passenger car engine. The wedge head was a fantastic passenger car engine and great hot street performer- but didn't have potential to dominate racing. Along comes the Ball Stud Hemi. Canted valves though not better than the Hemi head design when going for all out racing were still very VERY good. So- not better than a hemi head BUT better than the inline c
valve wedge head. But the big bonus for Chrysler was the Ball stud used stamped steel rocker arms mounted on a rocker arm stud. Supe super inexpensive to make and reliable. Many aftermarket companies offer a Girdle for rocker arm stability when the RPMs and spring pressures begin to show the stud mount designs limitations. But the Mopars version of a 396 Chevy had a deep skirt B block that is incredibly strong where as the chevy has the crankshaft well below the oil pan mount surface. What could have been. I grew up having a confrontational rivalry with chevy guys- they were all arrogant, hated mopars and were loud mouthed. But The BBC is a force to be reckoned with- at least when it comes to building the engine into the big power High RPM stages. Tons of affordable aftermarket support to remedy any issues that arise during this journey and I imagine this rang true all the way back to the late 60s early 70s as well.

Still love the wedge engines, but The five gen 3s I have had, have all been good ones too. One with about 250,000 miles before I sold it.

Still preparing a proper home for my first gen 2 build.

Yeah, that’s impressive but I’m still partial to the early junk

Can't beat the Hemi for eye candy in a engine bay!