Speed killed Paul Walker, not mechanical problems.

A source connected to the CHP reportedly told TMZ a speed analysis showed that driver Roger Rodas was going between 80 and 93 MPH on Nov. 30 in Southern California when he lost control going around a curve and crashed.

The Associated Press quoted an L.A. County Sheriff's Department source who also said mechanical failure was not at fault. Investigators reportedly found that the tires were nine years old. Shortly after the crash, law enforcement sources reportedly told TMZ they were the original tires and hardened, meaning they lost traction on the road.

TMZ reported in December that Porsche issued a memo to its dealers nine years ago warning that the 2004 Porsche Carrera GT could be dangerous to an untrained driver. The memo said the car was so sensitive, it needed to drive on smooth surfaces. "This vehicle cannot drive over a Foster beer can that is lying on its side," it reportedly said.

Investigators also reportedly said an aftermarket exhaust system had been installed, which would have increased the engine's horsepower. The coroner's office said neither Walker nor Rodas had alcohol or drugs in their system.

Contact Tony Hicks at Facebook.com/BayAreaNewsGroup.TonyHicks or Twitter.com/insertfoot.