The last pump gas 572 hemi I built made 800 HP at 6500 RPM on Oregon 92 octane non ethanol pump swill. it had around 10 3/4 to 1 compression ratio and a top end kit from Stage V heads from FHO along with one of there cams for EFI, Stage V single plane dual 4150 flange with a set of 1150 CFM dry throttle bodies with a Holley EFI kit from Rich at Fastman EFI
Nothing special in the motor as the car will have air conditioning, cruise control power steering and power brakes
This motor is going into a 1971 Challenger street and local drive to the local car shows car, customer wanted a "Hemi"
I call the 426 Hemi motors Hemiroids for a reason
Good luck on yours, they are basically a internal combustion motor after all