In case anyone wants to hear what an old pushrod Firehawk from the early 90's sounds like on the HPT dyno...
https://youtu.be/lCHdhw9A2Pc?t=36s
FWIW, we ran a calculated 320 HP & 404 LB FT at the flywheel, which seems a bit low on the HP and a bit high on the torque if you compare to what the manufacturer advertised. That said, it still feels like an absolute kick in the pants to stomp on it. So that's satisfying.