I tend to lower the steering ratio because I like to have a more responsive GT3 when I turn my wheel while putting very little angle.
Don't hesitate to raise the steering ratio by 1-2 clicks if you are used to playing with more steering ratio.

TC: - I recommend the TC6.
      - TC5 if you master the Mustang traction
      - TC4 at the exit of the turn 7 (Tosa)

HotLap/Qualifying lap adjustement:
- Target psi tyres 27.0-27,1
- Rear Toe: decrease one click (or more) if you want more turning OR increase one click if you want more stable
- Rear Ride Height: increase one click if you want more turning OR decrease one click if you want more stable

Race adjustement (advice):
- Target psi tyres between 27,2-27,4
- Rear Toe: decrease near to 0
- Rear Antiroll Bar: decrease one click if you want more stable but understeer can appear 
- Rear Ride Height: increase one click if you want more turning OR decrease one/two click if you want more stable
- Front Brake Ducts: it depends on the temperature
- Rear Brake Ducts: it depends on the temperature

My best lap with this setup: 1:39.397 (on a mega lap, there is the possibility of doing .3 low or even .2 mid high)

Good Luck and Have Fun.

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