Roger,
I have driven these roads many times and it wasn't until last month that I learned about this 1915 race taking place.
Thanks for allowing me to ramble on once again, I hope to start work again within 2 weeks.
The Start / Finish line was set up towards the end of a two mile straight along Rosecrans St. and the main grandstand was situated to show spectators the cars going by at their top speeds around 100 MPH. But many of the crowd assembled at the corners as they wanted to see the action at those points.
Some scenes of the start to the 1915 race.
(Note the winning Stutz # 8 started away back in the field. )
Waiting for the flag to drop. The # 3 Tahis has an interesting torpedo shaped extra coolant reservoir above the engine.
Temperatures and tempers are rising in this photo of the start as the cars are about to head north along Rosecrans.
Air pollution apparently was not an issue back then !
The start line area today looking north along Rosecrans St towards the first corner.
The start line area today looking back south along the Rosecrans two mile straight.
(Ken H..)