Normally a low-budget independent, McDuffie entered into a partnership with Donald Magnum and purchased a chassis from Richard Childress Racing.

As a result, McDuffie skidded across the grass and hit the Armco outside retaining wall and tire barrier with such force that the car rebounded into the air, rotated 180 degrees, and then came to rest upside-down.

As the cars got back on the track and cruised under yellow flag conditions, the media attention turned to Chip Williams, NASCAR's PR director, who disclosed that McDuffie had died instantly from head and brain injuries.

[10] McDuffie's sponsor, Medford Speed, hired accident investigators, Phil Moser and Terry Shaw, to determine the cause of the fatal injuries.

The report cited a "black tar-like substance" on the window and damage to McDuffie's helmet foam and microphone tab that was consistent with a tire from the barrier entering the car upon impact.

[11] McDuffie's death led to changes at Watkins Glen and also influenced motorsport safety changes that would come to full fruition at the end of the decade.

Six weeks earlier, Camel GT prototype driver Tommy Kendall had a hard crash in the same section during the Camel Continental VIII, when a wheel failed on his Pratt & Miller Intrepid RM-1-Chevrolet prototype, sliding into the barrier, breaking both his legs and sidelining him for the rest of the 1991 season, including the Winston Cup race, where he was set to substitute for Kyle Petty, injured at Talladega in May (Kendall had substituted for Petty at Sears Point earlier in the year).

Also, at the time, basilar skull fractures were the subject of developing research by Jim Downing and Bob Hubbard into a head and neck restraint for motorsport.

Downing, a champion sports car racer, and his brother-in-law Hubbard, were in the process of developing the HANS device, which had just begun production.

The judge in that case ruled that McDuffie was familiar enough with the track to be aware of the dangers and that mechanical failure caused the accident.

From McDuffie's death in 1991 to 2001, notable stock car drivers such as Dale Earnhardt, Adam Petty, Blaise Alexander, and Kenny Irwin Jr. would also die from crashes that caused basilar skull fractures.

In modern times most motorsport sanctioning bodies worldwide (including NASCAR), mandate drivers to use head and neck restraints.

McDuffie made Sanford, North Carolina home; the city supported him through struggles much like it did with hometown driver Herb Thomas.