Not bad. I once made it from Amarillo, TX to Albuquerque, NM in 2.5 hours in a 1970 Hurst-Olds 442.
1972, Amarillo, TX, to Columbus, OH in 24 hours and five minutes. Driving a Honda 600N Coupe running on 10” Bridgestone radials and powered by a two cylinder transverse mounted motorcycle engine. $1600 brand new off the showroom floor in CA. Damn thing got almost 50mpg on the highway. Of course, every little crosswind was a lane change...