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. On the GTR'18, I recommend 14 maximum.

TC: - I recommend the TC1 to be safe.
    - TC off if you master this car

ABS: - I recommend the ABS3 to be safe
     - ABS2 if you are good on your trail braking 

HotLap/Qualifying lap adjustement:
- Front Target psi tyres at the end of the lap 26,8-27,0 
- Rear Target psi tyres at the end of the lap 26,8-27,0
- Front Toe: decrease near to -0,20 if you want more turning OR increase near -0,15 if you want more stable (it depends on the feeling of player)
- Rear Toe: increase near to 0,02 if you want more stable
- Front Antiroll Bar: decrease 1 click if you want more turning OR don't touch
- Rear Antiroll Bar: increase 1 click if you want more turning OR don't touch
- Front Bumpstop Range: increase 1-3 clicks if you want more stable OR don't touch
- Rear Ride Height: increase 1 click if you want more turning OR decrease 1-2 click if you want more stable or don't touch

Race adjustement (advice): Adjust based on race duration. For 15 minutes, you can keep the qualifying setup. For endurance with a 1h/1h10 stint, opt for a slower setting for pure performance but consistent over the duration of the stint.
- Front Target psi tyres at the end of the lap 27,0-27,3 
- Rear Target psi tyres at the end of the lap 27,0-27,3
- Front Toe: decrease near to -0,20 if you want more turning OR increase near -0,15 if you want more stable (it depends on the feeling of player)
- Rear Toe: increase near to 0,02 if you want more stable
- Front Antiroll Bar: decrease 1 click if you want more turning OR don't touch
- Rear Antiroll Bar: increase 1 click if you want more turning OR don't touch
- Front Bumpstop Range: increase 1-3 clicks if you want more stable OR don't touch
- Rear Ride Height: increase 1 click if you want more turning OR decrease 1-2 click if you want more stable or don't touch
- Front Brake Ducts: it depends on the temperature
- Rear Brake Ducts: it depends on the temperature

My best lap with this setup: 1:34.740 (on a mega lap, there is the possibility of doing 34.5 high, so you can improve so much my time)
Best lap with 80L: 1:35.500 (average time 35.7 at the stint start /on a mega lap, there is the possibility of doing 35.3 very high)

Good Luck and Have Fun.

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