Any top quality engine you look at will have shaft type rocker arms on it, whether it's NASCAR, NHRA or Bonneville racing. The reason is they are the strongest, most reliable rocker arm money can buy.
These include fully machined aluminum rockers, premium centerless ground shafts and needle bearings, alloy fasteners and tool steel lash adjusters.
For S/B Chevy with 23-degree valve aftermarket heads.