I worded my comment very poorly, Ridox. I meant modifications that do not involve adding, changing or removing car parts and such. Otherwise we would be saying that AC Tuning is similar to Gran Turismo's Tuning. The simple fact of the matter is, if someone is looking for a game that lets them add turbos, perform "weight reductions", tweak LSD settings, adjust anti-roll bar settings and suspension settings on EVERY car, then Assetto Corsa is not the game for them.
Race cars allow for much more tuning whereas street cars are treated to be more like the car you would get from a dealership, 100% stock. Occasionally, Kunos will provide a tuned version of their street cars. If I'm not mistaken, they always use the designation S1 - S3 to imply Stage 1 tuning or Stage 3 tuning, for example. There are also a few cars that come in a tuned version called Drift. Take a guess at what that implies...
I am a huge fan of Tiago Lima's work. Is it 100% perfect? Of course not. He's a dude in a basement building or converting tracks for a video game as a hobby, not a profession. He is not privy to the information that professional developers are. Personally, I think that the sudden incline before Turn 1 at Tsukuba needs to be fixed. I knew something was off on my very first lap of Tsukuba. Maybe some day he'll get around to doing something about it, maybe not. Until Kunos gives us a laser-scanned version of Tsukuba or someone else builds a better Tsukuba circuit for AC, I'm going to have to deal with some imperfections on mod track creations and I'm perfectly fine with that. If I could do better I would, but I can't, so I take these free mods with much appreciation for the modders considerable efforts in recreating these amazing race tracks.
EDIT: You asked if Assetto Corsa simulated EBD. I don't believe so. Otherwise I'm sure it would be talked about. I would be surprised if any sim does. Real ABS systems are insanely complex computer systems. I'd be willing to bet that ABS implementation in all racing sims is grossly simplified to be included at all.