After this, and earlier posts saying something similar, I entered this event with some trepidation.
One try - used a stock Fiat 500, and was in the lead by the end of the first lap - the cars behind started to close, but didn't catch me before the uphill section on the second lap. I finished 7 seconds ahead of P2.
The key seems to be getting a good slipstream from the start, and then a good run up the hill on the first lap - the AI seem to really slow down up there, but are then unbelievably fast down the hill! And yes, the final turn is a bit tricky, and can lose you a lot of time.