Good advice and you're quite right. Think I'll take advantage of it

have you got any hard data on how grip is affected by temperature for different rubber compounds todd ?
otherwise the discussion is somewhat irrelevant since as stan said you can drift perfectly well with hot tyres in lfs so theres not necessarily a problem that needs to be adressed ... at least not anytime soon

I think I read once, that Falken produced a tire especially good for drifters in a way. But I can't remember where or when, so I can't say for sure. I'm a drifter too, and I like the idea about more smoke, but not the one about new tires with less traction. As said: I like the challenge about having control of your car!

Quote from Shotglass :

have you got any hard data on how grip is affected buy temperature for different rubber compounds todd ?

Quote from jtw62074 :

Drifters in LFS need a tire that loses about as much grip in reality due to temperature as a real tire does. Who cares what the temperature is at the end of that or how quickly it heats up? It will heat more or less to an equilibrium temperature at some point and stay there lap after lap. At that temperature, on a street tire the grip should not be some 70% of the "optimal temperature."

Do they? But indeed if it gets back to something this basic, then this issue should be affecting racers (grippers) also. But I must admit I can't recall regular complaints from racers that the tyres lose grip too quickly when running above their optimum temperature. I also don't think the tyre physics suddenly use a different model when you suddenly throw a car sideways. I think it's a given if you push your tyres too hard you're gonna cook them and suffer for it Also the atmospheric temperature and the road surface temp play big roles in determining tyre temperature and grip values. LFS is locked at around 20degrees I believe. Pretty chilly!

Scawen obviously has data which he based the coding off.. and unless he's willing to share it and compare it to yours I don't think this debate is going anywhere

To sum up.. drift tyres don't exist, except for those coloured smoke ones, however even they probably don't offer any advantage over any normal tyre.. the debate that the whole lfs tyre model is flawed probably doesn't belong in this thread.

Quote from jtw62074 :

would you mind sharing it ?

Quote from Matrixi :

In real life, drifters don't use any special tires really. Well some do use those that create red smoke.

But in D1 for example, they are using Bridgestone Potenzas (not sure if Neovas are used), which are just normal high-class sports tires. Not designed for drifting, but for sporty grip driving.

So that's a -1 from me, we don't need them.

I think Neovas are used in japan. At least they were used (Taneguchi used them). D1 UK winer was dusqualified on the otherhand becauzse he used neovas which are illegal in the UK. IIRC at least.

EDIT: Smoke is a setup thing. SOme setups produce little smoke, Chris (.Inc) made a setup once, that made 'huge' amounts of smoke.

Quote from Takumi_Project.d :

Do they? But indeed if it gets back to something this basic, then this issue should be affecting racers (grippers) also.

Indeed. It's ironic there's actually a debate going on between two supposedly opposing sides when this would simply benefit everyone, isn't it?

Quote :

But I must admit I can't recall regular complaints from racers that the tyres lose grip too quickly when running above their optimum temperature.

How would they know?

Quote :

I also don't think the tyre physics suddenly use a different model when you suddenly throw a car sideways.

Of course it doesn't. Nor would it have to.

Quote :

I think it's a given if you push your tyres too hard you're gonna cook them and suffer for it

That's a problem. Physics by polls and popular non-scientific consensus does not equal reality. What really happens to a street tire when it wears a few 1/10ths of an inch off the tread?

Quote :

Scawen obviously has data which he based the coding off..

Obviously? How so? Because there's a curve there? I know a bunch of guys that do the same thing and it's not based on real data at all. There isn't much of it out there.

Quote :

and unless he's willing to share it and compare it to yours I don't think this debate is going anywhere

That's fine, I understand how the relationship between grip and temperature and so on works. If one chooses not to believe that, I'm not twisting arms to change anyone's mind.

Quote :

To sum up.. drift tyres don't exist, except for those coloured smoke ones, however even they probably don't offer any advantage over any normal tyre.. the debate that the whole lfs tyre model is flawed probably doesn't belong in this thread.

I disagree that it doesn't belong here. As for the first comment, I covered that at least three times now so won't repeat myself again.

Quote from Shotglass :

would you mind sharing it ?

Sorry, I only share that sort of thing with Doug Milliken, Gregor Veble, and Chris West.

I think that what jtw says makes sense. And he has proven many times that he knows what he's talking about. If I had to trust someone about physics, that would be him. Enjoyable posts to read as always.

Todd - I appreciate your depth of theoretical understanding on these subjects, but I honestly think you're off track on this one. Perhaps the current implementation of temperature vs grip is totally wrong - this doesn't mean a more realistic tyre degradation model would be 'useful' for drifters. I have no temperature data from my experiences, but I do know it didn't take many laps at fairly moderate slide angles / power output, to completely destroy a set of harder compound street tyres - to the point where I had to stop or trash the guards on my car.

You destroyed the tires, that's fine and happens. What happened to the lateral grip before then? Did they heat up and suddenly you couldn't do the same lap times as before? Notice any significant drop off in cornering speed? Where these tires the ones that were recommended for the car or did you pick out your own off the shelf?

I know a fellow that worked on the Firestone tread separation case a few years back as a mediator between Ford and Firestone on behalf of the government. He told me what the tire data looked like both before and after the tread was completely removed from the tire, including a lot of the cords. Yes, the tire was destroyed, but what happened to the grip is probably not what you'd think. Nothing theoretical about real tire tests.

This isn't an issue of tire destruction, really. You can let the tire cool back down and you'll regain the grip in the sim. Different scenario from what you're describing, I think.

Someone could just mod the normals or something.. to make it less grippyer and more smokey.

seems my sugestion flew over everyones head

good read...you people know what your talkin about

the only thing that bothers me is that i thought...(for instance in drag racing...plz don't flame this thread cuse of it but...) that tyres gain grip at higher temps due to the tyre melting(causing it to stick to the road and adding to greater off the line acceleration)...anyways...(yes i read the whole thread)

It bothers me that the LFS community can't come to agree on things that shouldn't affect other types of racers (drag/drift/grip)...and just flame for the sake of..NOTHING just becuse they can't come to appreciate that they are more types of racing out there. .Overall the idea of having tyres that smoke at the point when u lost grip isn't that bad lol ooh and even come with a new tyre texture :P ?

My Opinion: in time when this game nears completion it may or maynot have made accomodations for the many different types of racing out there.

Ill wait and find out.

Quote from jtw62074 :

You destroyed the tires, that's fine and happens. What happened to the lateral grip before then? Did they heat up and suddenly you couldn't do the same lap times as before? Notice any significant drop off in cornering speed? Where these tires the ones that were recommended for the car or did you pick out your own off the shelf?

This was on a 15 year old sportscar, I dunno if they bother to recommend for those, but they were certainly not 'sports' tyres. You're right that I didn't notice much change in grip until the tread blocks peeled off. I've never noticed any change in grip on road tyres except from cold to warm to destroyed - but then I also have no idea just how hot I've got real 'sports' tyres. It does seem that even my proper 'sports' tyres, when treated in a similar fashion, were heading down the path of destruction without noticeably losing grip. spots of what looked liked blistering, chunks out of side tread, etc.

Quote from jtw62074 :

This isn't an issue of tire destruction, really. You can let the tire cool back down and you'll regain the grip in the sim. Different scenario from what you're describing, I think.

Sure. I was more responding to your argument (or at least, what I thought it was ) that more accurate physics would be be
useful for drifters in terms of tyre life...

Quote from Blowtus :

This was on a 15 year old sportscar, I dunno if they bother to recommend for those, but they were certainly not 'sports' tyres. You're right that I didn't notice much change in grip until the tread blocks peeled off. I've never noticed any change in grip on road tyres except from cold to warm to destroyed - but then I also have no idea just how hot I've got real 'sports' tyres. It does seem that even my proper 'sports' tyres, when treated in a similar fashion, were heading down the path of destruction without noticeably losing grip. spots of what looked liked blistering, chunks out of side tread, etc.

Right..

They do get super hot, no question. I've helped out in the pits for friends at a couple of bomber races on a 3/8 mile oval. To show us how hot the tires and rims would get and illustrate that we should never try to grab the lugnuts with our fingers or touch the rim, after one of the guys took a flat tire off he threw a cup of water on it (the tire was flat from running over debris). It instantly turned into a cloud of steam, boiling right on the rim in a flash, so they get plenty hot and do so very quickly. It had to be at least 100C for that to happen of course, and probably much hotter since it pretty much vaporized the whole cup in seconds.

What's notable about it is during those races a lot of the guys are sliding the cars around like crazy coming out of the turns. I mean big angles, like 15-20 degrees pretty frequently, for two or three hours on end. Neither of the guys I was with that were driving complained at all that the tires were going off or anything like that even though they were hot enough to boil water on the rims and had been semi-drifting for hours on end on the same set of old, used tires. Basically the grip stayed the same as far as the poop-o-meter could tell until the tire came apart, which happened pretty rarely even during a three hour race. If I recall correctly, one of the tires had worn clear down to the cord near the shoulder and yet the driver didn't notice any change in how the car was driving. This is more or less what you found too, it would appear. Damage/blistering/chunking? Sure, it happens. Although it didn't happen to us with those particular cars and tires.

EDIT: I just remembered that this was a three hour enduro event where there was indeed a pit stop at the half way mark. So the wear and so on above was after an hour and a half, not three hours.

I've seen a fair amount of force data on street tires at varying states of wear and most people would be quite surprised at what really happens there. As a sim developer, some detailed things I prefer to keep to myself, but let's just say that having a tire in LFS that doesn't lose any grip until it hits the cords is not unrealistic at all, and may be more typical of street tires than anyone would ever want to believe, especially after spending so much time driving tires in many different road racing sims that totally give up after they get a bit too hot or wear down a little bit.

There are pretty well known reasons in the industry why tires do or do not lose or gain grip as they wear down or their temperature changes. This is primarily rubber property related and is a big part of the art/science of compounding. Tires can be made to do pretty much what an engineer wants them to do.

From the test data I've seen both on tires and specific rubbers, having a tire in LFS that is basically insensitive to temperature and doesn't lose grip as it wears down (until it's running on the cords or fails of course) isn't unrealistic at all, and has nothing to do with making a special "drift tire" for LFS. That's pretty much how real street tires work, so it would benefit both the racers and the drifters, and overall make racing on street tires more realistic and true to life.

It's a win-win situation for everybody. However, if the non-drifters argue against it because they like having to nurse their road normal/super tires so much and believe that's how NR and SBR functions when it's put in the thread, well... The ones driving imaginary tires aren't the ones that are in here requesting drift tires.

Anyway, my point is just that having a tire like described is actually a very realistic thing and is more typical of real street tire behavior. It's not some sort of "special drift tire" at all. Is there something wrong with having street tires in LFS that lose grip perhaps linearily as they wear down, or lose grip in a hurry as they get past their "optimum temperature?" Not really. I like it that way too because you need to be more careful with the cars and take care of the tires, and it gives more fun stuff to play with and think about in terms of setting up the car to keep the temps where you want them. Tire designers can make tires do pretty much what they want them to do. Well, road supers and normals are specially designed Scawen brand street tires, and real tires can be made that way too so they're still perfectly realistic in this regard even if they might not be so typical. But for drifting, a more typical street tire would be useful so the grip isn't changing dramatically as you go from one corner to the next and so on, and you don't wind up with miniscule levels of grip after a short time. Would such a tire be a realistic addition? Absolutely.

Drifters don't need a "special drift tire," they just need a "slightly more typical street tire." Racers could benefit from it too.

I don't drift in LFS so this is all no big deal to me really. I'm just trying to make an argument on behalf of those that want to do it and show that there might not really be a big conflict here or "realism clash" after all between the drifters and racers. When I want to go drifting I do it here in my own little ugly sim

http://www.performancesimulations.com/files/ToddSim19a.wmv

Now, where's that LX-8?

Interesting post - your sim makes nice noises and seems to respond well
I'm all for realism. Sometimes though compromises need to be made, if tyre degradation such as I described is not easily modelled, perhaps a tyre that responds more violently to temperature change is a suitable compromise, from the drivers perspective? Of course I doubt we'll ever know the motivation behind each and every bit of physics in LFS

Thanks for the compliment.

Yeah, that'd probably work just fine. Just keep the grip vs. temp curve flatter and then at some really high temp, make the wear rate go way up and the grip go way down, or just drop the grip a bunch and don't worry about the wear rate. One can of course do a more involved model then that, but that's not a bad one at all really and the players wouldn't know the difference either way. They just expect to fry the tires at some point and have things get slippery.

I didn't read all that post but I have sugestion. When you put new server you can choose which car you can run in it. Do it the same with tires, for example:

- racing tires: yes/no
- drift tires: yes/no

Then you are able to choose what kind of tires is avaible in specific server.

How simple is that !!!!

As u see it..... Its a SIM... To Simulate Racing/Drifting/Motorsport.... Real Drifters use "Racing Tyres" so you are asking for something that is not a real thing HENCE the Drifters saying -1.... You are asking for a Imaginary Item in a Racing SIMULATOR

Sorry buddy...
Good Finkin Though... Find something real though

I've been keeping up with this thread even though this is my first contribution to it. Its, after all, always facinating to read one of Todd's posts about tyres.

I think that for now, with the incomplete tyre wear model - ie. wear doesn't really affect grip unless you pop the tyre - the temp vs. grip curve needs to be a bit more steep than it should be so as to make strategies a bit more interesting. I expect this to change as graining, blistering, chunking and whatnot are simulated.

I also expect different tyre compounds in the different makes of tyres with different sidewall stiffness/thickness, thread thickness, compound and everything. You'll probably find that these will be suited to different driving styles and tracks (I expect tarmac qualities to change from track to track also at some point). One of them will probably be more suited to drifting. I don't see anything wrong with that. They won't necessarily be "drift tyres", just another compound. You'll probably find that in real life, there's some tyre that's really suited to drifing whilst another will struggle.



EDIT: Dodgybro, you are talking out of the wrong hole - no-one has asked for drift tyres since its been established that they don't exist. Rather, several compounds, one particularly suited to drifting. However - you'll also find that these will also be used for a race at some point. I don't expect you to know much about the FZ50 or Raceabout being a demo racer but on some tracks, the rears start overheating and then you start sliding more and more and loosing more grip and it becomes a vicious circle. Tyres like this might be handy there.

Why would tyre wear ever affect grip? On a slick tyre, it's just another layer of identical rubber on an identical surface.

Treaded road tyres on the other hand should gain grip as they wear, since you will be increasing the contact patch. The reason tyre wear is bad on road cars is that a) less tread depth means more interesting wet handling and b) with normal road driving, tyres age - by the time you've used up most of your tread, the rubber could be a few years old, and the handling characteristic could begin to get rather funky. Hence new tyres feel much better - it's not related to the tread depth (much).

Edit: regards to tyre heat and grip, there is obviously some affect, otherwise race tyres would not be heated, cold tyres wouldn't be a problem, and there would be no optimum temperatures. Scawen was obviously aware the effects had been over done, patch T/U reduced the temperature-grip sensitivity somewhat from patch P/Q.

Quote from Bob Smith :

Treaded road tyres on the other hand should gain grip as they wear, since you will be increasing the contact patch.

not necessarily ... im to some degree convinced by my own observations that thread has a similar effect on dust as it has on water