The Porsche carrying "Fast & Furious" star Paul Walker was traveling about 90 mph when it went out of control on a suburban street and crashed, killing the actor and his friend, a Los Angeles County Sheriff's Department spokesman said on Tuesday.
The sports car driven by Roger Rodas on Nov. 30 slammed into a light pole that had a 45 mph speed limit sign and several trees before bursting into flames.
Walker and Rodas died at the scene.
Investigators concluded that unsafe driving, not mechanical problems, caused the crash, said LA County Sheriff's Department Cmdr. Mike Parker during a press conference.
"She saw a red sports car driving westbound on Kelly Johnson Parkway at a very high rate of speed. She did not know how fast, but said the car was 'sucking asphalt' and was very loud. She said that the car was 'jiggling' back-and-forth in his lane like the driver was jiggling the steering," a witness statement read.
Investigators calculated that Rodas was driving between 80 mph and 93 mph when his 2005 Porsche Carrera GT began to drift after coming out of a curve.
It had an aftermarket exhaust system that would have increased the engine's horsepower. It had tires that were 9 years old, Parker said.
Neither Rodas nor Walker had been drinking or doing drugs, Parker said, citing toxicology tests.
The Associated Press reported in December that investigators had found no evidence that the car had mechanical problems and ruled out debris or other roadway conditions.
Subsequently, Porsche sent engineers to California to review the rare car's wreckage. Though it was badly mangled and burned, the engineers were able to do a thorough analysis. They found no problems with the car's electrical systems, brakes, throttle, fuel system, steering, suspension or other systems.
Porsche declined a request for comment Tuesday.
The conclusion about the speed was based on a "yaw" mark that one of the car's tires left on the road in an area of industrial office parks in Santa Clarita, about 30 miles northwest of downtown Los Angeles. Witnesses told a sheriff's deputy that they thought the car could have been traveling in excess of 100 mph.
Post-crash investigators noted several issues with the condition of the car, which had several prior owners, including IndyCar driver Graham Rahal:
—Its original exhaust system had been modified in a way that could allow it to go faster, but also could have been done to change its sound.
—Its tires were about nine years old; the owner's manual suggests changing the tires after four years.
—Its left rear brake rotor was worn below manufacturer specifications, but that did not contribute to the crash.
Rodas, 38, and Walker, 40, had taken what was supposed to be a quick ride from a fundraiser benefiting Reach Out Worldwide, a Walker charity that gives first-response aid to victims of natural disasters. The crash occurred near the fundraiser, and horrified friends of the men raced to the scene.
While Rodas was Walker's financial adviser, the two had bonded over their shared love of fast cars. They co-owned an auto racing team named after Rodas' shop, Always Evolving, and Rodas drove professionally for the team on the Pirelli World Challenge circuit in 2013.
Walker starred in all but one of the six "Fast & Furious" blockbusters, which glorify muscular cars and risky driving.