The 40-year-old Walker was riding in a red Porsche GT about 3:30 p.m. when the sports car flew off the road and slammed into a tree in Santa Clarita, authorities and witnesses said. The car burst into flames.Jim Torp, who was also at the event, identified the second victim as Roger Rodas, a pro racer and father of two who owned Always Evolving Performance Motors. Torp described how Rodas’ 8-year-old son tried to save his dad.