How Much Horsepower Required to Cruise Comfortably at 70 MPH?

dibbons said
I must be over thinking this thing. I do know the factory only offered the 340 vehicles with 3.23 or lower (3.55 etc.)

that was due to being part of the "performance package". I had a '75 Dodge truck with a slant six that came with 3.90 gear. Not that it cruised better at 70 mph with them … LOL