I have done a few manufacturer races and the Elise event in London was the hardest so far. I made up most gains post Trafalgar Square. That is in part because I still suck early in the lap (which I partly blame on the DS2 Sixaxis), and it is IMO easy to be very aggressive in the second half of the lap (either that or the AI is just not so good at that part of the track).
On my winning run I took the lead at the start of lap 3, then actually got a good line through T1, but got rear-ended from the AI car and received a penalty ! That penalty system is frustrating at times.
I used the untuned 111R because at that time I did not know there was a tuned version in the Concept dealership.
SetUp; as a twisty circuit I changed the gear ratios to focus on acceleration rather than top speed, and I put the front and rear springs up a couple of notches. Aids off except TC at 2.