Neil is correct - not unusual.
But I keep coming back to the M60 BMW 3 liter V8. Yeah, not as cheap as a small block, but -
4 valves, DOHC, compact, huge HP upside potential, modern casting techniques, serviceable short blocks readily available.
And they run smooth as a baby's bottom.
The only real issue I see would be figuring out how to ditch the hydraulic valve actuation and go with a mechanical set-up.