Those are some very good numbers and it does not take much to make good street friendly power out of a big block. I built a 511 for my 72 C20 that runs on pump gas with Edelbrock Perf RPM heads, Perf RPM Airgap intake, Demon 850 carb and a Crane Roller cam. And it makes all of its power down low. Very impressive feeling when driving it. I wish my dyno guy was able to give me a graph but I settled for this print out.
Not bad, it makes 671 ft lbs at 4200 rpm and 588 hp at 5200 rpm. The dyno pull started at 3200 rpm and it was already making 648 ft lbs. Like I said, it is fun to drive.
It has Air Conditioning and a Turbo 400 auto with 4.10 gears. And a Gear Vendors so I can run the highway at 70 mph.