Blunt force trauma and thermal trauma were given as the official causes of death for Dunn, 34, and Zachary Hartwell, 30. Dunn's 2007 Porsche 911 GT3 burst into flames after going off the road around 2:38 a.m.
Toxicology reports will come back in four to six weeks, a coroner's spokeswoman said.
The car might have been traveling more than 130 mph in the 55-mph zone when it jumped a guardrail, flew into a wooded ravine, struck a tree and burst into flames, police told Radar Online on Tuesday.
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I've never seen a car destroyed in an automobile accident the way this car was even before it caught on fire," West Goshen Police Chief Michael Carroll said.
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The automobile actually came apart."
"Proving Ground," the G4 series in which amateur daredevil Dunn re-created stunts from movies and video games, was put on indefinite hiatus Monday, according to Deadline.