As is usual with me, I started finding 25.80x T1s last night, but couldn't replicate either T2 or particularly T3 and despite hitting T2 in 50.3xx a few times, I was always getting 1.11.5xx at the next split!
So frustrating - I always improve in one sector at the detriment of another.
My current time is holding up ok - setting a goal of a 1.10.8xx with a strong t4 for this week. I love this track but I've never raced it with a relatively slow car - this car obviously is NOT slow, but I'm talking LMP1/2 or hypercar experience in Forza Motorsport 3 for example!
My tips in light of DS3 usage:
1.) Active steering helps - I've tried mild & strong & off - I "tend" to be unable to control the car as well without it and that leads to a few tenths here and there - particularly in the first sector. If you can handle the first sector without it, my advice would be to not use it.
2.) BB - If using Active Steering, I've used 4/6 BB - with AS off, something along the lines of what Dan suggested (6/6) seems more appropriate - you want to get a bit more rearward action with it on, less so with it off as you will get it by default.
3.) TCS - even with a pad (using triggers for accel/brake) - TCS at 0 is best. You need to feather the throttle, particularly in T1, but I am 2 tenths quicker to the T1 split regularly with it off and I struggle to get past 26 flat with it on. You really don't need it with this car IMHO, even with a controller.
4.) ABS - Tried all combinations of ABS 1, 2 and 3 - didnt seem to make much difference, I'm using 1.
5.) Gearing - turn 1 stay in 2nd and stay tight, feather the throttle to avoid too much oversteer, but you need SOME to get you pointing in the right place. Turn 3 I take in 3rd gear and often dip into the sand, you can maintain almost 80mph through there with a perfect line. T5 is one of the most important corners - flick down to 3rd and chuck it in, trying to run over the small bit of curb, dont worry if you catch the sand slightly - maintaining the speed up the hill is the main thing. Corkscrew - this one is a pain, you have to run over the curb on entry to be able to put the power down early, but it's hard not to spin up a bit here...or spin entirely. Corner after the corkscrew I feather round at ~ 77/78 mph, penultimate turn I flick down to 2nd to engine break, then back to 3rd for exit - final turn, same thing, but use 1st and flick to 2nd to power out - 1st gear only hits 40mph or so, so it's not enough to keep it engaged for long, just to engine brake.
all this is fwiw - nothing gospel, im not that good