Edit: this is probably better:
https://www.gtplanet.net/forum/showthread.php?t=285460
Analysis of a round, with strategy to come close to the fastest you can go through the corners.
Warning: I'm a slow driver, some fast people might be able to give better tricks. I'm far from doing a lap like this (ever).
Trick: to go really fast you should almost only concentrate on breaking/steering/throttle, all the rest should be natural (have talent or concentrate just on this race)
Trick: for wheel users adapt the options (simulation, for me force feedback 6, sensitivity -1, + TCS =0 every time you go in)
Trick: shift down quickly when decelerating, Gran-Turismo is quite unsensitive on doing this too early.
Trick: prefer to shift before accelerating out of corners, it will give you more control on a fast lap.
Based on Ti-tech85 2:17.137 run:
https://www.youtube.com/watch?v=mbDFNceDSAU
I do not mention full throtle and go up to rpm limit from now on. Speed in kmh (Ti-Tech) - mph (Tigney).
1st corner: Entry speed: 204 - 27
Break/Turn point: 2sec after board, notice only 2 small break inputs
Lowest speed: 160 - 98 Lowest gear: 4
Acceleration point: middle of corner in 4th
Trick, steer in as if you are going to turn before the corner, you will slide through.
3st corner: Entry speed: 190 - 117
Break point: 1sec after board or some meters before the red/white band, notice it goes fast to subtle break input
Lowest speed: 76 - 48 Lowest gear: 2
Acceleration point: middle of corner, start with subtle throttle
4th corner: Entry speed: 109 - 65
Break point: I have not figered it out yet, just do it on feeling, again, not a lot of breaking
Trick: go sufficiently wide so you can line up the car for the acceleration
Lowest speed: 64 - 37
Lowest gear: 2
Acceleration point: middle of corner, in 2nd start with subtle throttle, not easy here
5th corner: shift just before and you can risk to cut it quite a bit (try to not cheat!)
6th corner: I had a tendency to go to 6th gear just before, but it is never needed.
Entry speed: 220 -132
Break point: a bit after the red/white sholder starts, gradually less breaking, look at small correction just before acceleration point.
Lowest speed: 91 - 58 Lowest gear: 3
Acceleration point: end of corner, in 3rd start with subtle throttle
7th corner: Entry speed: 120 - 74
Turn point: do not break yet, just before the tarmac changes colour
Lowest speed: 76 - 46 Lowest gear: 2
Acceleration point: end of corner, in 3rd start with subtle throttle
9th corner: Entry speed: 216 - 134
Break/Turn point: 2.5" after sign, breaking fades away quickly
Lowest speed: 141 - 88 Lowest gear: 4
Acceleration point: just before middle of corner
11th corner: Entry speed: 212 -132
Break/Turn point: just past the middle of corner 10
Lowest speed: 165 - 103 Lowest gear: 4th
Acceleration point: when stable in the next straight, early after apex
12th corner: Entry speed: 168 -105
Break point: just on feeling, quite fast after 11
Lowest speed: 138 - 81 Lowest gear: 4th
Acceleration point: just a bit after the middle of the corner
13th corner: Entry speed: 142 -84
Break/Turn point: a bit before the red and white hard sholder
Lowest speed: 112 - 70 Lowest gear: 3rd
Acceleration point: 1/4 into the corner
15th corner: Entry speed: 232 - 144
Break point: 1.5" after the sign
Lowest speed: 117 - 72 Lowest gear: 3rd
Acceleration point: middle of corner, gently
16th corner: Entry speed: 185 - 115
Break point: before the sign
Lowest speed: 78 - 43 Lowest gear: 2nd
Acceleration point: a little bit before the apex
17th corner: Entry speed: 90 -57
Break point: don't break
Lowest speed: 85 -57 Lowest gear: 3
Acceleration point: 3/4 throttle at apex
How to improve from this: You do not get faster from wanting a lower time, you need to pick-up speed.
In "make or break" corners you should be at the right speed, check your replay (and speed at next breaking point).
1) Corner 1
2) Corner 4, sets up for the long straight
3) Corner 7, sets up for the long straight
4) Corner 9, very fast, need to keep the speed
5) Corner 13, sets up for the long straight