Assetto Corsa Competizione update 1.9 is out now, and it's a big one.
The latest patch update makes some major changes to the physics, so you may need to update your existing setups. Coinciding with the update is the release of the 2023 GT World Challenger DLC Pack.
Without further ado, let's look through the patch notes to find out what's new in Assetto Corsa Competizione update 1.9
Physics changes
Tyre model
As Kunos Simulazioni’s Head of Vehicle & Handling R&D Aristotelis Vasilakos revealed in his recent livestream, update 1.9 makes some major changes to the tyre physics in ACC. Tyre pressure ranges are now wider from 26psi-27psi in update 1.9. Essentially, you won’t find the perfect grip at 26.5psi any more.
Lower pressures will give more flex, traction, and movement while generating more heat. Higher pressures, on the other hand, will give you more lateral support, precision, and generate less heat.
Temperature ranges are also be wider with a 70°C-100°C core. This means camber and toe will have a more noticeable effect on how the temperature spreads across the tyre surface. Alignment choices will also affect heat generation.
Because the new physics allows for more rotation, setups with negative toe will no longer be necessary. Previously, negative toe gave performance advantages in update 1.8, but Kunos felt this was unrealistic.
Suspension
Update 1.9 also brings numerous suspension changes. Suspension bumpstops will have maximum compression travel of 20-30mm instead of compressing infinitely.
Before, springs would ride the bumpstops continuously in custom setups, bringing the car lower to the ground and reducing drag. As a result, released energy from the bumpstops would cause the car to bounce on kerbs.
This will no longer happen in update 1.9 as the bumpstops stop compressing after a short travel.
In addition, Kunos Simulazioni has improved the damper simulation in update 1.9. Altering slow-speed damping stiffness will not have a noticeable effect on handling and the fast damping simulation has also been improved, affecting how the suspension reacts to high kerbs, bumps and undulations.
Force feedback
Accompanying the changes made to the tyre and suspension model are adjustments to the force feedback. Excessive negative toe at the front will now result in vagueness around the centre. At the rear, this will provoke fishtailing during braking.
Conversely, a positive toe at the front and rear will offer more steering wheel stability but less agility. Changes to tyre pressures will also influence the sidewall movement.
Low tyre pressure results in softer sidewalls and requires more steering input, while higher pressures will require less steering input.
2023 GT World Challenger DLC Pack
Launching alongside update 1.9, the 2023 GT World Challenger DLC Pack is also available now. The DLC includes three new GT3 racecars: Ferrari 296 GT3, Porsche 911 GT3 R 992, and Lamborghini Huracan GT3 Evo2.
You can also race them on Circuit Ricardo Tormo, a new track also included in the DLC.
The 2023 GT World Challenger Pack is priced at £10.99 on Steam. Kunos Simulazioni has confirmed it will be available on consoles "later in 2023."
Assetto Corsa Competizione update 1.9 patch notes
You can find more details in the Assetto Corsa Competizione update 1.9 patch notes patch notes below via Steam.
General
- Added Circuit Valencia Ricardo Tormo as DLC content.
- Added new Lamborghini Huracán GT3 EVO2 as DLC content.
- Added new Ferrari 296 GT3 as DLC content.
- Added new Porsche 911 (992) GT3 R as DLC content.
- Added a batch of new liveries for the 2023 GTWCH season.
Gameplay/UI
- Added controller preset for Moza steering wheels.
- Added support for new DLC track content in custom championship (via Open Series).
- Fixed track selection not respecting user-defined order in Open Series championship mode.
- Adjusted AI skill level for a number of gold and platinum-ranked drivers.
Graphics
- Fixed an issue with certain cars receiving an incorrect visual offset in their pitstop position.
Physics
- Updated Mercedes AMG GT3 EVO with latest advancements, features, and more.
- BOP work
- Improved tyre model
- Improved tyre flex
- Improved tyre heat generation
- Improved tyre rolling resistance simulation
- Improved tyre footprint simulation
- Wider tyre pressure range (slicks 26-27psi)
- Wider tyre temperature range (slicks 70°C-100°C)
- Improved bumpstops simulation
- Improved suspension end of travel simulation
- Improved dampers simulation
- Improved electronics logic (TC1, TC2, ABS)
- New variable engine braking simulation (Huracan EVO2)
Improved aeromap simulation on yaw and roll.