"Jason Leffler was a great racer and an even better friend," Stewart, the three-time NASCAR Sprint Cup Series champion who was once a teammate of Leffler's at Joe Gibbs Racing, said Thursday. "To not have him around to talk about whatever race one of us had just run, or were going to run, will be hard. My thoughts and prayers go out to his family, especially his son, Charlie, who Jason loved more than anything."
The 37-year-old Leffler, a two-time winner on the NASCAR Nationwide Series, died Wednesday night after the crash in a heat race in a 410 Sprint Car event at Bridgeport Speedway, a 0.625-mile, high-banked dirt oval about 15 miles southwest of Philadelphia.
A spectator, 40-year-old Chris Taitt of West Deptford, said Leffler had been in second place, apart from other cars when his winged car slammed into a wall at the fourth turn. Taitt said the wing was "flattened like a pancake" and the seat appeared to be displaced.
The sprint car event was the track's highest profile event so far this year, with better-known drivers, more expensive tickets and a bigger prize — $7,000 — than the usual Friday and Saturday night events.
Sprint car races can be dangerous for drivers and spectators, with many facilities lacking the SAFER barriers that are standard in NASCAR and IndyCar
Three drivers were killed last month in crashes on dirt tracks. Driver Josh Burton died of injuries sustained in a crash at Bloomington Speedway in Indiana; and two drivers were killed in a race in Nevada. In March in California, two people were killed when a car careened off a dirt track and crashed on pit road.
Leffler's representative, Spire Sports, said funeral arrangements are being made.
"Despite his many accomplishments, Jason still followed in the same footsteps of his heroes that would race anything, anytime. All Jason wanted to do was race. He was the life of every party and a true racer," Spire said in a statement. "We will miss Jason dearly and know that his family appreciates all the thoughts and prayers."
Panther Racing Owner John Barnes, for whom Leffler raced in 2004 and 2005, said the racer had a "fierce competitive spirit and a devilish attitude. Jason was a small man with a huge right foot."
From Long Beach, Calif., Leffler made 423 starts in NASCAR's three national series, winning the two Nationwide races and one Truck Series event in a career that began in 1999. He also made three IndyCar Series starts, finishing 17th in the 2000 Indianapolis 500. Leffler won three consecutive USAC Midget championships from 1997-99 before following mentor Stewart's path into NASCAR.
Leffler's last full NASCAR season was 2011, when he ran the entire Nationwide schedule for Turner Motorsports. He finished sixth in the standings that season and hadn't had a steady NASCAR ride since.
The driver had been racing dirt car events most of this year. On Sunday, he finished last at Pocono in his lone NASCAR Sprint Cup start of the year, running only eight laps in a start-and-park ride.
Many drivers included the hashtag "LEFturn" in tweets mourning Leffler. That was his nickname and was written above the driver's side window on his race cars.