I agree with Tristan in that I think the tyre model is very good as it is, aside from the obvious low speed grip issue...

I have read race drivers comments that driving at the limit does feel very much like the average person would expect driving on a wet road to feel, when you are near the limits of traction it doesn't take much to over do it our main problem and the problem of all sims is the lack of seat of pants feel which often makes us slow to react in a sim.

Having said that I do think there is some small issues at the limit which affects handling, and if I was to take a punt at what it would be I'd say [I "think" that the changes in the slip angles between front and rear tyres and even left and right tyres has a small issue when the tyres are in the different states (grip, tread walking, no grip - I don't know proper terms), which affects the handling of the cars at the limit also how slip angles are affected differently between the free rotaing wheels and driven wheels]. But I have every confidence Scawen will be able to identify any areas that need improvement and then come up with away to do it. It's hard for us to identify as we simply don't have the information or tools necessary to determine anything useful (without scientifc test instruments any observations we make are still very subjective and therefore most likely flawed) Scawen does have or is able to get the necessary tools and info though as he is able to code tools (tyre test rig) and can obtain data to compare it too.

I don't actually see the current tyre model as having bugs but as improve it a little more and it will go from being awsome to absolutely awsome and that's why I look forward to the next physics patch

Now as for S3 tyre models I look forward to seeing brake heat simulated (which heats the tyres) and the current tyre heat model revisited, also more refinement in the differences between the treaded tyres and slicks (e.g. how dirt sticks to different tyre types and how the different tyres react in the transition phases of grip to loss of traction, also I guess the relationship between lateral and longitudinal grip [traction circle] would vary for different tyre types also) and then there is the track

Another problem I have seen.
In real life:
If you get into a rear-wheel-drive car and hold the break and give the car gas (clutch work is involved) the front tires will grip as long as you want, while the back tires will slip. This is a very common practice for drag racers who want to warm up their rear tires before a race. And even with drag car with large rear tires and smaller front tires, because the rear were quickly put into traction loss, the smaller fronts can keep traction and not slide -- this of course is only to a point, eventually the rear tires (if large enough or with soft enough compound) will over power the front tires' grip.

In LFS:
I use pedals with the break and gas pedals being on separate axis. I have tried to do burnouts on RWD (I'm pretty sure I used one of the GTR RWD cars -- I can't remember, and I am not home to check) cars by holding the break, holding the clutch (not necessary), giving gas, then releasing the clutch. The result is the rear tires squealing and the front tires (if the break is pressed enough) sliding while locked up. So I messed around with it a bit trying to give my front tires better traction -- slowly letting on the break, get them right to traction loss without going over; but to no avail. I went into the setup and even put R4s on the rear, and R2s on the front. But still the front tires just slide.
I find this all very odd, because the rear tires with complete traction loss (only slipping friction) have more traction than the front tires with no traction loss -- and these cars, in general, should be front heavy, so the front tires should have more traction than the rear innately.

Well, you are nearly there.

IMO, this is easily fixed with the setup, you maybe just tweaked the wrong settings. Try putting brake bias forward as well. Another factor is that in much of the setups for LFS they are setup for racing, and generally have quite a tall 1st gear. So try shortening 1st gear to give the rear wheels more torque.

I usually don't have any bother pulling a burnout if I want to, and if I can't it is usually the setup.

Yeah, but my point is that this shouldn't be a problem at all.
The traction of the "stable" front tires should overwelm that of the rear tires which are in traction loss.
The diference between traction and traction loss is too little. This is why people who "slide" around corners in LFS are able to keep up with those who keep the car in alignement. In real life, if you are getting your backend out at all around corners, you'll be all but left in the dust.

I don't know if anyone ever saw this post I wrote, but this is about the only problem I have with the tire physics/model in LFS (and generally how it is right now with focus on road cars)

http://www.lfsforum.net/showthread.php?p=66005#post66005

Seeing that we also have low-speed grip issues as well and all....

But this is all primarly on the issue of having pre-heated tires. As if it was used to hide even wierder low-speed physics at cool temperatures.

And Bob's quote here sums it up kind of:

Quote from Bob Smith :

Yeah it's weird the tyre pressures have swapped since S1. While it used to be "set them as high as they would go", now it's "set them as low as you can without melting them".

Quote from bobbfwed :

Another problem I have seen.
In real life:
If you get into a rear-wheel-drive car and hold the break and give the car gas (clutch work is involved) the front tires will grip as long as you want, while the back tires will slip. This is a very common practice for drag racers who want to warm up their rear tires before a race. And even with drag car with large rear tires and smaller front tires, because the rear were quickly put into traction loss, the smaller fronts can keep traction and not slide -- this of course is only to a point, eventually the rear tires (if large enough or with soft enough compound) will over power the front tires' grip.

In LFS:
I use pedals with the break and gas pedals being on separate axis. I have tried to do burnouts on RWD (I'm pretty sure I used one of the GTR RWD cars -- I can't remember, and I am not home to check) cars by holding the break, holding the clutch (not necessary), giving gas, then releasing the clutch. The result is the rear tires squealing and the front tires (if the break is pressed enough) sliding while locked up. So I messed around with it a bit trying to give my front tires better traction -- slowly letting on the break, get them right to traction loss without going over; but to no avail. I went into the setup and even put R4s on the rear, and R2s on the front. But still the front tires just slide.
I find this all very odd, because the rear tires with complete traction loss (only slipping friction) have more traction than the front tires with no traction loss -- and these cars, in general, should be front heavy, so the front tires should have more traction than the rear innately.

In LFS even with clutch help off and the clutch on an axis there is still Auto clutch issues to deal with. In LFS it is not possible to stall the car so if the car is put in a position that will stall the engine the clutch will activate itself. Watch the clutch bar and see if it moves when you try to do a burn out

Quote :

In real life, if you are getting your backend out at all around corners, you'll be all but left in the dust

Ok, not hanging out the rear end, but every car needs some amount of working slip angle to corner. The smallest working slip angles are 2 degrees with IRL cars on ovals. Most high end downforce race cars have a working slip angle of 3 or 4 degrees. Bias ply slicks as used on most non-downforce cars are higher still.

The other issue is that optimal cornering grip is achieved with some tire slippage. Do a web search for "traction control race", and you'll find that most modern traction control systems allow some amount of slippage, instead of just stopping the slippage. Typically the slippage is 8% to 12%. This might be something a driver can do for a short period, like a qualification lap, but not for an entire race, which is why modern traction control systems produce better lap times.

Of course there are a few high end race series that don't use traction control, like USA Champ Cars (formerly CART), and Nascar, but then again, with the ECU's, it's difficult to check for. Nascar tries to monitor engine exhaust sounds to try and detect traction control. Most of the high end race classes do allow traction control, and even "club level" racing, such as Mazda prototype (like Indy lights), or Dutch Supercar Challenge, where the only rules are power to weight ratio limits for each class, otherwise there are no restrictions at all (active suspension, XTRAC sequential shifters, traction control systems that use individual wheel sensor / braking and engine ecu, ... are all allowed).

One issue is that in real life, it's difficult to detect if there is traction control. http://insiderracingnews.com/jf111802.html

Anyway, this is a bit off topic. I think the real issue is that it's not possible on a PC to truly simulate the dynamic physics of a tire / contact patch, so some sort of simplification has to be made.

With real life racing, optimal lap times occur with some slippage, which is one issue racing games have a problem with. In addition, in order to drive at the limits, a driver is going to spend a significant amount of time beyond the limits, and the car has to be forgiving enough to allow this.

In a racing game, the cars need to be more forgiving than in real life, or else a player just ends up memorizing control inputs, which is not a good thing, since the goal of any racing simulator should be to simulate a real world racing experience, where you can go reasonably go beyond the limits without incident, even if the physics has to be modified a bit in order to accomplish this.