changelog from the iRacing forum, you gotta love the very last sentence:
AI Racing
- The following tracks have been enabled for use by AI Racing:
- - Kansas Speedway - Oval
- - Michigan International Speedway
- AI Drivers have received additional training at the following tracks:
- - Lime Rock Park - Grand Prix
Heat Racing
- Fixed an issue with Events that do not include Heat Sessions where the top Qualifiers were not gridded inversely when this setting was specified.
Audio
- Gear shift and backfire sound levels have been improved for all stockcars, including:
- - ARCA Menards Chevrolet Impala
- - NASCAR Cup Series Chevrolet Camaro ZL1
- - NASCAR Cup Series Ford Mustang
- - NASCAR Cup Series Toyota Camry
- - NASCAR Xfinity Chevrolet Camaro
- - NASCAR Xfinity Ford Mustang
- - NASCAR Xfinity Toyota Supra
- - [Legacy] NASCAR Cup Chevrolet Impala COT - 2009
- - [Legacy] NASCAR Cup Chevrolet SS - 2013
- - [Legacy] NASCAR Cup Ford Fusion - 2016
- - [Legacy] NASCAR Nationwide Chevrolet Impala - 2012
- - [Legacy] NASCAR Xfinity Chevrolet Camaro - 2014
- - [Legacy] NASCAR Xfinity Ford Mustang - 2016
- - [Legacy] NASCAR Xfinity Toyota Camry - 2015
Spotter
- Default Spotter calls for numbers during lap timing have been improved.
Peripherals
- XInput is now supported for Serafim R1+ wheels.
CARS:
Audi RS 3 LMS
- Tire compound has been adjusted to slightly reduce wear.
Ford GT - 2017
- The duration of the compressor run for pneumatic gearshifts has been increased to 3.0 seconds to prevents overlapping. Also reduced the pressure drops at each actuator fire, which reduces the frequency of fire for the compressor.
NASCAR Gander Outdoors Chevrolet Silverado
- Season setups have been updated.
NASCAR Gander Outdoors Toyota Tundra
- Season setups have been updated.
Street Stock
- Fixed an aesthetic issue with some metal on the window net.
TRACKS:
Dover International Speedway
- Some signs, billboards, and advertisements have been updated.
Talladega Superspeedway
- Fixed a flag that would not obey the wind.
AI Racing
- The following tracks have been enabled for use by AI Racing:
- - Kansas Speedway - Oval
- - Michigan International Speedway
- AI Drivers have received additional training at the following tracks:
- - Lime Rock Park - Grand Prix
Heat Racing
- Fixed an issue with Events that do not include Heat Sessions where the top Qualifiers were not gridded inversely when this setting was specified.
Audio
- Gear shift and backfire sound levels have been improved for all stockcars, including:
- - ARCA Menards Chevrolet Impala
- - NASCAR Cup Series Chevrolet Camaro ZL1
- - NASCAR Cup Series Ford Mustang
- - NASCAR Cup Series Toyota Camry
- - NASCAR Xfinity Chevrolet Camaro
- - NASCAR Xfinity Ford Mustang
- - NASCAR Xfinity Toyota Supra
- - [Legacy] NASCAR Cup Chevrolet Impala COT - 2009
- - [Legacy] NASCAR Cup Chevrolet SS - 2013
- - [Legacy] NASCAR Cup Ford Fusion - 2016
- - [Legacy] NASCAR Nationwide Chevrolet Impala - 2012
- - [Legacy] NASCAR Xfinity Chevrolet Camaro - 2014
- - [Legacy] NASCAR Xfinity Ford Mustang - 2016
- - [Legacy] NASCAR Xfinity Toyota Camry - 2015
Spotter
- Default Spotter calls for numbers during lap timing have been improved.
Peripherals
- XInput is now supported for Serafim R1+ wheels.
CARS:
Audi RS 3 LMS
- Tire compound has been adjusted to slightly reduce wear.
Ford GT - 2017
- The duration of the compressor run for pneumatic gearshifts has been increased to 3.0 seconds to prevents overlapping. Also reduced the pressure drops at each actuator fire, which reduces the frequency of fire for the compressor.
NASCAR Gander Outdoors Chevrolet Silverado
- Season setups have been updated.
NASCAR Gander Outdoors Toyota Tundra
- Season setups have been updated.
Street Stock
- Fixed an aesthetic issue with some metal on the window net.
TRACKS:
Dover International Speedway
- Some signs, billboards, and advertisements have been updated.
Talladega Superspeedway
- Fixed a flag that would not obey the wind.