To everyone who is into simulation, and the pursuit of realsim. I mean realism. (If you are fresh weekly content drooler, ten minutes "tryer", and judging cars physics by how perfect the model looks, then don't read) Hello, I have been studying tires for a while. Studying them in AC, studying them in real life, comparing. Reading books, articles, works, observing videos and so on. I am definitely not saying that I know a lot about tires right now, but a little bit for sure. Tire, as Paul Haney writes, is one of the most complex devices. I am not assuming that these things which I am going to mention are wrong in the code in AC, or they are wrong in the parameters of car physics .ini files, maybe those things are wrong in combined ways, or they are not wrong at all, just they seems so to me. Also in my opinion some cars are more believable than others, I don't know if some are nailed better by Aris, or the codes written by Stefano fits some cars better. I think older AC cars are better. But it must be mentioned that there are ton of official cars in AC, "kunos quality" is a known thing, and indeed overall AC quality is very consistent, but I hink that some things are just a bit better in some places than the others, especially speaking of such complex subject as vehicles physics, of which the tire is probably the biggest secret. 1. Tires grip falloff In my opinion most if not all AC tires has too little falloff, or I could also say too much falloff grip. That thing alone makes driving much more zoned, drifting less of a thing. Every time you go too much over the slip angles or ratios, greater falloff makes you take more effort to keep the car in precise control, or in control. greater falloff makes rear end more tending to "run away" as you spin your tires out of slower corners, oversteering makes you move your arms faster, locking tires under braking is more of an issue. Transitions from oversteer to neutral slides to regained traction is more noticeable with also variations of back and forth - as you might have an oversteer switching to neutral little slide and back to oversteer again if you put the power down too soon... Few little examples: This twitchyness is very much the falloff of grip, cold tires makes it extreme. Not a drift missile at all, even though obviously it loves slip angles, but it is not a drift car. Of course we could argue that there could have been oil, which ofcourse would make for great grip drop. This is absolutely insane. Again lowish temps makes it more extreme, afaik it was 12C then in GW. Also you might say that we have more advanced GT40 with wider tires in AC, but I think it still should behave at least a little bit like that. 2. Tires load timing Now this is rather complex. Tires doesn't react instantly to inputs, they have relaxation length phenomenon, also a bit of flex. Moreover, front tires are always a bit ahead of rear tires in terms of timing because they are steered, and.....in front. Rear tires has a bit of delay on top of fronts. Also often we have rear tires wider which also makes front vs rear tires behavior slightly different, and timing too. Relaxation length depends on load and slip angle, more load more length to react, more slip less length to react. Lateral tire flex is more influencing narrower tires, because logically particular amount of deflection will be more noticeable if it relates with narrower tire, visually and physically too. Tires load timing contributes to putting more effort in choosing turn in point, cars slides feels less linear, wheels feels more individual, coming back from slides gives slight speed wobbles unless you make inputs very very well. If a car has scrub radius flex and relaxation lengths can amplify it quite a bit. Few little examples: 0:17 This Superperformance GT40 wobbles like crazy, it is combination of how tires falloff and then regain grip and the tires timing goes. 0:20 this old thing realy maginfying the phenomenons. You can see front vs rear are moveing very much on their own, they seem like they has their own inertia each and they oscilates in different way, it oversteers > understeers > oversteers > understeers till it clears the turn. I think many cars moves like this when on the very limit, especially if driver like to be a bit more rough, I think even modern cars does that, just with way lower, perhaps sometimes even invisible motions, well sometimes maybe very visible... 3. Grip and load sensitivity I think some tires/cars in AC feels like if they have too low static grip and then too little incremental grip curve drop as the tires gets loaded very unevenly in high speed turns. Sometimes low speed bend feels a bit too slippy, and high speed bend feels a bit too safe. It is very tricky stuff, I am just thinking. For example Nordschleife karousel is not a very fast corner, it also has very big banking in concrete part inside. So it is not a fast corner, and because of great banking tire loads will be more even, thats why you should be able to be surprisingly fast there, sometimes it feels that you are not so much in AC. Also it is concrete surface, in terms of surface it is not going to be more grippy than tarmac I think, adhesion might be better, but not mechanical keying - rubber penetrating irregularities. Higher neutral grip, and more grip loss because of load sensitivity in combination with grip falloff levels and speeds plus manipulating wheels timing with flex and relaxation length might be a nice touch, and I believe a realism improving touch in many cases. I am glad if you actually read it all, I know I don't have a reputation as someone who "knows things", but I think it is always awesome to think, share and discuss.