Fly Car by John Fuller

Ten-year-old Eli Martin would do just about anything to spend more time with his dad. But Dad’s working overtime to save Martin Motors, the family’s struggling car company. One day Eli and his best friend, Earl, stumble on a classic cherry red sports car produced by Martin Motors back in 1984, hidden away in the family’s barn.
Eli starts to wonder: What if the red sports car could actually fly? A car like that could save his dad’s company—and send their relationship soaring to new heights. With the help of his family’s faithful groundskeeper, Grady, Eli starts to put his plan into action.