Tool · Setup

Setup Doctor — tell me what feels wrong.

No downloading someone else's numbers. Describe your handling problem and get ranked changes — each one with an explanation of what it does.

What is your car doing?
The idea: You trade a little top speed for a car that never surprises you. A beginner is faster overall in a predictable car. Every lever below is given in the direction of stability.
Quick start, no tinkering: In game, load the car's “Safe” preset → put the tyre pressures in the window → brake bias 1–2% forward → a few clicks more rear wing → TC/ABS up → leave the dampers and the diff alone for now. Done.
Stability levers
Character of the beginner cars
Tyre pressure window (dry): aim for ~26.5–27.0 psi hot at all four corners. Start a few psi lower when cold and let them build over 3–4 laps. In the middle of the window you get the most grip and the most predictable behavior at the same time.

Every adjuster, and which way it works. No more looking things up across five forums.

In short

The setup doctor reverses the usual order: instead of downloading someone else's numbers, you describe how your car feels wrong — understeer on turn-in, oversteer on the throttle, instability under braking — and you get ranked, concrete changes, each with an explanation of what it does.

For a safe, forgiving car in ACC the directions are: tyre pressures inside the window (~26.5–27.0 psi hot), brake bias slightly forward, TC and ABS higher, more rear wing, softer anti-roll bars. Because ACC's physics has been unchanged since version 1.10.0 of 1 April 2024 — everything after that was content only — these directions no longer go stale with every patch.

Common questions
How do I fix understeer in ACC?

Check the front tyre pressure first (too much pressure kills the contact patch), then soften the front anti-roll bar, soften the front springs, add a little toe-out and move the brake bias slightly rearward for more rotation under trail braking.

How do I fix oversteer on the throttle?

Lower the differential preload (the rear wheels start to differ earlier), raise the TC, soften the rear anti-roll bar, add more rear wing and increase rear rebound so the rear tyres stay loaded.

What is the right tyre pressure in ACC?

Aim for about 26.5–27.0 psi hot on all four tyres. You start a few psi lower cold and let the pressure build over three or four laps. In the middle of the window you get the most grip and the most predictable behavior at the same time.

Do I have to redo my setup after every ACC patch?

No. The last ACC patch with physics changes was version 1.10.0 on 1 April 2024; everything after it — up to the current 1.10.4 from December 2025 — only brought liveries, wheel presets and seasonal content. Only the occasional BoP adjustment shifts optimal pressures and ride heights slightly; the stability directions stay the same.

As of: ACC v1.10.4 (Dec 22, 2025)Good news: nothing has changed in the physics or the tyre model since v1.10.0 (April 1, 2024); everything after that was content — liveries, wheel presets, the 2025 GTWC season. So what is written here does not go stale patch by patch. The stability directions would be patch-proof anyway; only BoP adjustments shift optimal pressures and ride heights slightly. Rule engine built on researched GT3 knowledge — no numbers guessed from someone else's setups.