Ofcourse I'll get around to answering your question
The way I lap in time trial is: the first session is just a feeler, I don't expect to 'get' it during such a stint so I'll experiment with different gears, techniques, drift, no drift, downshift to help braking, ect. Then the 2nd session I'll use this knowledge to arrive at the basic idea of what is required to achieve the limit in a velocity sense.
With this combo the 1st corner is a bit of a make-shift corner as you can induce a drift (as Zoky has probably done in his epic .417 T1 split) or you can drive smoothly and only aim for a high .4 at best, the second corner I'm looking to enter fast (100+km/h) and let the car dip just below 100km/h before powering out, the following right hander, I position the car to the extreme left of the track, just dipping the left wheels into the sand (with this car dropping a few wheels in the sand when exiting surprisingly has absolutely no effect on the speed!) and maybe a tiny dab of the brakes, attempting to perform a powerslide at around 125/126km/h, just holding on to it in the sand as I exit.
You should be seeing 145 146km/h as you leave the sand, thats when you know you have solid exit speed. The next left is a very hard corner to take at the limit, you have to exit at 100km/h exactly, and avoid snap oversteer when exiting, requires a good rythm to know the immediate steering angle required to achieve maximum turning performance without oversteering, dont be afraid to hit the sand when exiting. The following left hander can be taken, using a bit of the inside rumble/and outside sand upon corner entry, at around 131+km/h, the most important part about this corner is to avoid hitting the sand If you can, its not critical but once you hit the sand you cant immediately steer back onto the track without risking a snap oversteer, and If you need to stay in the sand you're going to loose the ideal line. The corkscrew is bloody difficult, what I do is I just brake as smooth as possible and hope the car starts rotating at the death of my braking, in 1st gear, sometimes it works other times it doesnt, exit at 68/70 and partial throttle for the right component, low 90's.
Doesnt matter If you're pushed wide upon exiting, you can still make a good fist of the double left, no brake just a downshift to 2nd at around 135, followed by an upshift to 3rd at around 123, exiting anywhere between 120-122 depending on your line, the following right is definitely a panic corner for me, you can downshift to 2nd, or stay in 3rd when braking, and take it at preferably 120+. last corner is a bit of a hit or miss affair, you need to induce a late drift under brakes and use ever inch of the inside rumble/sand, in an attempt to exit at just over 60km/h in 2nd, after an intial downshift to 1st ofcourse. Had a few good laps ruined there because of 3 wheels in the sand.
As I lap I monitor the speedo closely during each corner, which is how I've been able to systematically arrive at the above speeds, and just before I accelerate out of each corner I will glance at the speed and make a quick judgment call on how much throttle/steering angle I'll apply when exiting. I never operate the ghost while cornering, just on the straights, its difficult to activate the ghost with the G27 anyway. Hope any of this stuff is useful and thanks for your question redreevos!