Aero smero. I just finished replacing some wheel bearings that had seen 500,000 miles and that helped the go fast a lot since it no longer rumbles. Maybe time to push it to 90!
LOL I thought I was hot stuff back in 1967 when I averaged 87 mph between Toledo and Cleveland on the Ohio Turnpike. That speed was calculated based on the time stamp on the toll card.
Bias ply tires, drum brakes, yadda yadda.