How many rpms does a 454 like on the highway?

[evan love]

Hello,

I have a 1979 single cab C30 dually with a rebuilt, but stock, 454 with and edelbrock carb and headers...

...th400 trans and 4.56 rear diff gears

And I'd like to drive it 1100 miles from my parents house to mine on major highways.

Any idea what rpm range these engines can do comfortably without any damage to the engine for long days on the highway?

Any thoughts on expected fuel consumption and top speed at a safe rpm for the engine?

Thanks,

Evan