@"Solo Man" Assetto Corsa is getting on in life, and whilst it is a great sim and I think it is a good decision to go with it, may I also suggest Assetto Corsa Competizione if you are serious about circuit racing. ACC is made obviously by the same team that developed Assetto Corsa, but ACC uses a more recent game engine with better physics, lighting etc. and is focused more on real world GT3 endurance championships such as the blancpain endurance series and the intercontinental GT championship. Meaning races can take place at night, day, or over the period of an entire day like the Spa 24 hour race, or the kyalami 9 hours. The original Assetto Corsa does not have a day night engine unfortunately.
There are GT3 and GT4 individual series as well as mixed series, meaning you can have GT3 and GT4 in the same race. Passing traffic becomes very fun at midnight on spa.
There is also a racing league in SA called Sim Race SA that uses this sim for the GT3 series of races.
Without going into to much detail, the sim takes all of the realism from Assetto Corsa and dials it up a notch. It is a lot of fun and uses a similar rating system to iRacing to monitor your driver progress for online racing. This keeps online races clean as crashing will negatively affect your safety rating etc. Every track in ACC is laser scanned, including a 2019 laser scanned version of Kyalami. Every single bump and crack is captured and felt through the Force Feedback system. If they are in the real world track, they are in the sim.
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