After just 27 of the 200 laps, a gear in Guthrie's engine broke; she finished 29th. A year later she finished ninth. But after starting 14th in 1979, a burned piston ended her race after three laps. She failed to qualify the following year.
The 1980 Daytona 500, where she finished in 11th place, was her last major race. "I didn't retire," she said. "I ran out of money. For the next three years I tried to find sponsorships and get back in the game. Finally I decided if I didn't cut it out I was going to jump through a window."
She moved to Aspen in 1985 and began writing her autobiography: Janet Guthrie, A Life at Full Throttle. She married American Airlines pilot Warren Levine in 1989. He was a charter jets pilot when he died of a heart attack in 2006.
"I was giving speeches before I stopped racing," she said. "Once in a while I still do. I like gardening. I go hiking in the summer. I lead a pretty ordinary life.
"I think I made a huge difference in how the men drivers felt about having a woman in the field. As time went on, that changed. I believe the men, with one or two exceptions, came to recognize that what I did on the track was just like what they did on the track."
Bruce Lowitt, a freelance writer living in the Tampa Bay area, is a former sports features writer for the Associated Press and the St. Petersburg Times.