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FlexibleFelix
02-11-2017, 05:02
Hi all! I'm new to the forums!

So not to start this in the wrong place (Forgive me if it is) but I noticed a lot of people have been saying that the tires overheat really easy lately in the forums and I've seen it a lot in GT3 cars. Figured I'd put this in a good place to share my findings on the subject.

(Get comfy this is a long read!)

So I run a basic controller on an Xbox One S. I love GT1 in this game and many other classes but I don't really understand how I run so much slower in GT3. Sure, it may just be me, not really the point of the post so no need to go there about it, but what it's had me do is seek out a really good setup for GT3 class.

Since pretty much the release of the game I've been working on getting a good GT3 tune. I know the 488 is good, and nowadays I run an Acura cos it seems to do just as well. But for about a week I worked on a 991 R tune, since I saw it do well when others drove it.

So I jumped in the 991 R endurance and ran it for a few laps at Fuji Speedway, setting up a simple tune and sure enough, it was really fast, but it'd overheat the rear tires really easily. I spent the whole week after that trying to tune it out, with the car getting faster and faster as I went, as well as easier to drive and more durable.

In the end I managed a setup that still runs fast, but only for 5 laps, on cold tires. There is also this thread from GTPlanet, which shed some light on the way the tires work, I'd definitely suggest checking it out. Unfortunately because I'm a new user I can't post it right now. I believe it's been posted on the forums before somewhere. Will post later when I find it. :)

So in the meantime, the summary of it is this: PC2 has shifted away from traditional tire physics in sims and gone for something much more 1 to 1 with real life. The execution isn't perfect no, but it's much more impressively real.

So for any tuners reading this, in line with the information in that thread, I've found that the tires will not change temperature much if at all if you change the static pressure in the tire, you'll only change how it contacts with the road in certain circumstances. I've also found that, like in the thread, you'll see that manufacturers in real life have optimal tire temperatures for the best performance. I haven't read it in a while but your typical 100 degrees Celsius (210 Fahrenheit) tire temperature is only good for hard slick tires. Soft slicks prefer colder temperatures around 85 Celsius (Not sure what that is in Fahrenheit sorry). When you run these compounds at around these temperatures, you'll tend to find you'll run the faster laps. Tracks that are too hot for example (Like Laguna Seca) will melt softs usually in GT3, so you'll need hard slicks.

Is there a drawback on hard slicks? Actually, no. My favourite part about this type of physics is that when you do run in Hard Slicks weather, you can run laps just as fast as soft slicks, they just need to warm up. Pre-race warming defaults the temperature above the soft slick optimum, so you can use the glitch that happens during that time where if you idle on the tune, you'll notice in the top right corner the tires will continue to increase in pressure, as well as drop temperature.

I haven't really noticed a *significant* difference in running the right pressure based on feel, but it does help smooth the cars a bit. It can however speed it up or slow it down from what I've seen, but not always. Sometimes it feels just as good on whatever pressure you had in the first place.


So, how does it all relate to the tires overheating and why?


Soon after I had tested and confirmed the above I went ahead and spent another day on the 991. Quickly I found out that the tires were overheating because they would scrub on a specific corner or two, causing more kinetic energy to build up in those tires and suddenly a jump in tire temperature (About 10 degrees Celsius give or take), leading to them overheating later from normal driving, since it then snowballs (ironic word huh?) into higher temperatures because it's not being given a chance to cool down. So the car will spin out sometime after that, in an unusual corner maybe or under brakes, completely looking like the car had nothing to hold it down over the overheating tire(s).

I should also clarify, it doesn't necessarily have to be at overheating temperatures. It can happen before that on softs.

So I went to the telemetry to examine the scrubbing and why it happens, and I think (ANYONE CAN BE WRONG) I see what's going on. When GT3 cars hit a turn, particularly a long corner, a big enough bump or dip in the road will cause the rear tire to lift off the ground somewhat, leaving it's set. So it's in the corner, gripping in a certain 'fashion' (Can't figure a better word for it) and it then lifts off because of the sudden road surface change. It then returns to the road, trying to once again, take a set in the corner and it can't do it. This is observed when you are mid-corner and all of a sudden for no rhyme or reason, you see tire smoke appear on one of the outside tires.

So watching the telemetry on this 991 R, I saw that in corners the car would swing and shift a lot of weight to this outside tire (or tires), giving it less ground clearance, to the point it will bottom out even. The outside tires would appear much hotter than the inside tires. I can't really explain it well (I could have a go if you want me to) but when this instance occurred, the scrubbing began. Either way, I figured this was how I could fix it, or at least I did this in other games, make the anti-roll stiffer so the weight wouldn't shift as aggressively, spreading the work of the tires more evenly over the car.

That didn't work. Despite the changes to the ARB, I didn't see any changes in the heat build-up in the tire, nor the rolling of the chassis. The game I've been told, simulates it very well. So, even after knowing this now, I had to try something else.

Try lowering the car? Stiffening everything up so it will sit as flat as possible? Play with the damping? It made it slower but I wanted to see the effect disappear...

Those didn't work either. At the very least, it only reduced the scrubbing, but that's probably because I wasn't able to drive as hard as before.

So I figured "Maybe just this car?" I tried them all, the 488 is much smoother and seems to not really encounter these issues as easily, but I can't drive it well enough to consider using it online.

This is why I use the Acura.

I went through all the other cars. Some weren't competitive, while the others would overheat over different tires (Usually the outer rear) and some are combinations of both!

So I went back to the 991 and to my best effort, I've landed a great setup for 5 laps on a mid-style track on cold tires. Make the track too hot and I can't run softs, I can run hards really well, but there's a big gap in the middle where the Porsche won't do well on either - too cold for hards and too hot for softs.

In the end I moved to the Acura. I've managed on a tune I mostly worked out in the first days after release to run really fast on a lot of tracks (I actually shelved it early on thinking it was really slow), and since it's not rear engined, it's rolling on both outside tires instead. It still scrubs, but it manages the heat much better. Not perfect, but way better. One day I may go back to the Porsche, but as it is I can't drive it on soft tires outside of short practice & qualifying stints. I can run that car really fast too, but oh well, still have my Acura.

So I dunno who I'm out to air this to, I figured maybe a dev might like to hear it, or maybe the peeps in here might appreciate this to better understand why some cars overheat? I spent weeks on this though, so I hope it is useful to anyone else out there. I'm no GT3 expert by any means, but perhaps more tire grip to prevent scrubbing? Less heat build-up? Better damping to absorb the bad bumps and dips? Smoother tracks? Just some ideas I think could fix it. I didn't try running asymmetrical setups however (EDIT: I've been told this could be really helpful). Maybe that's the workaround? I'm not game to try those though. I want my car to feel the same left as it is right you know? And not have more than 7 setups per car (Which a lot of you probably think is already a lot! Lol).

Steering wheel users shouldn't be as much affected by this versus pad (Unless you run a pad with really smooth steering). Not to say wheel users don't get this problem, but should manage it a little better with smoother steering and control. A number of people I know on wheels say they don't experience it quite as bad as I do, hence why I'm saying it. I can always be wrong! :P

Some classes I don't think are really affected either. GT1 for instance, my favourite class, I don't see this occur much if at all. The tires can scrub but the cars seem to run the tires better overall. Could be for many reasons, depends on the depth of the simulator really.

Anyways, hope you all liked my findings. Again, hope this helps!

FlexibleFelix
02-11-2017, 05:29
Ok I found the thread on here for the link (Only because I can't post links yet. Will update later.)
In the thread 'Project CARS 2' > 'The Garage - Car Setup Talk' > 'Tire temps pcars 2'.
The third post, has the link I was referring to above.

Also, if it's preferred, I can record this occurrence for you all. It should be pretty easy to pick up on it though. Just randomly any car could start producing smoke on one or two of the tires for no reason. If you watch in chase cam, you'll see the specific tire look like it hits a bad bump or something while in the middle of taking a corner in a rather stable state.

Course again, I can always be wrong. I don't want to sound like I'm all knowing, but I've done my best to realise it.

If I find out anything more on this too I'll update it later! :D


EDIT: I've updated the above post and this one to better reflect the occurrence based on feedback I've heard. I was wrong about the ARB being involved in the occurrence. Thanks for the input, Discord peeps! :)

Keena
02-11-2017, 06:53
Excellent post OP. Good job.
There's so much detail that it'll take 24 hours to go through it properly.
It's refreshing to find such a detailed post which strikes such a factual tone :)

Keena
02-11-2017, 07:08
Quick question- I suppose you tried increasing soft bump to stop the weight transfer?

FlexibleFelix
02-11-2017, 07:32
Quick question- I suppose you tried increasing soft bump to stop the weight transfer?

Yes. I went across all the settings I could on the Porsche. Nothing seemed to prevent the weight transfer. I didn't try however (As I pointed out above) an asymmetrical setup. Propping up one side could very well fix it.

I wouldn't really think the normal player would know to do this though. I was just stubborn about not doing it personally (Still am a bit lol).

Keena
02-11-2017, 07:41
Yeah it feels a bit un-natural. Also dialing in the fast bump to ensure constant wheel contact might help. Failing that potentially driving around the problem? Slow in fast out so that the higher speed section is a shallower angle of turn- not always possible. That tyre smoking issue has happened to me on occasion and it's been hard work to dial it out. Sometimes succesful sometimes not. Ultimately I've ended up just taking the corner slightly slower sometimes. As you say it's easier with a wheel. I'm in work in an hour so all I can say is good luck :)

FlexibleFelix
02-11-2017, 08:09
Also dialing in the fast bump to ensure constant wheel contact might help.

The Porsche doesn't have adjustable fast bump or rebound. The irony lol.

I thought exactly the same thing though. If it did have it I'd have tried it, but I also read in these forums that the Porsche has almost the same, if not identical(?) fast damping to the slow damping, so that's probably why it's not adjustable.

LockeChris
02-11-2017, 08:30
Wow you're dedicated! Now what I would like to know is, if a dev reads this: Does this issue exist IRL too? I mean maybe it does and we just don't know about it! Real pros and teams sure know how they would have to handle such issues and it might even be normal business for them, who knows?

Bealdor
02-11-2017, 08:55
Soon after I had tested and confirmed the above I went ahead and spent another day on the 991. Quickly I found out that the tires were overheating because they would scrub on a specific corner or two, causing more kinetic energy to build up in those tires and suddenly a jump in tire temperature (About 10 degrees Celsius give or take), leading to them overheating later from normal driving, since it then snowballs (ironic word huh?) into higher temperatures because it's not being given a chance to cool down. So the car will spin out sometime after that, in an unusual corner maybe or under brakes, completely looking like the car had nothing to hold it down over the overheating tire(s).

Open your (rear) brake ducts so your tires won't get too much heat from them.


So I went to the telemetry to examine the scrubbing and why it happens, and I think (ANYONE CAN BE WRONG) I see what's going on. When GT3 cars hit a turn, particularly a long corner, a big enough bump or dip in the road will cause the rear tire to lift off the ground somewhat, leaving it's set. So it's in the corner, gripping in a certain 'fashion' (Can't figure a better word for it) and it then lifts off because of the sudden road surface change. It then returns to the road, trying to once again, take a set in the corner and it can't do it. This is observed when you are mid-corner and all of a sudden for no rhyme or reason, you see tire smoke appear on one of the outside tires.

So watching the telemetry on this 991 R, I saw that in corners the car would swing and shift a lot of weight to this outside tire (or tires), giving it less ground clearance, to the point it will bottom out even. The outside tires would appear much hotter than the inside tires. I can't really explain it well (I could have a go if you want me to) but when this instance occurred, the scrubbing began. Either way, I figured this was how I could fix it, or at least I did this in other games, make the anti-roll stiffer so the weight wouldn't shift as aggressively, spreading the work of the tires more evenly over the car.


Raise your rear ride height (small effect on handling) or stiffen your rear springs (huge effect on handling) to avoid bottoming out.
Riding on your bump stops will render most of your suspension adjustments useless because the suspension can't work at all.


So I went back to the 991 and to my best effort, I've landed a great setup for 5 laps on a mid-style track on cold tires. Make the track too hot and I can't run softs, I can run hards really well, but there's a big gap in the middle where the Porsche won't do well on either - too cold for hards and too hot for softs.

If it's too hot for softs and too cold for hard tires, you should go for the hard ones and adjust your car setup to be more aggressive.
Harder suspension, smaller brake ducts, etc...


So I dunno who I'm out to air this to, I figured maybe a dev might like to hear it, or maybe the peeps in here might appreciate this to better understand why some cars overheat? I spent weeks on this though, so I hope it is useful to anyone else out there. I'm no GT3 expert by any means, but perhaps more tire grip to prevent scrubbing? Less heat build-up? Better damping to absorb the bad bumps and dips? Smoother tracks? Just some ideas I think could fix it. I didn't try running asymmetrical setups however (EDIT: I've been told this could be really helpful). Maybe that's the workaround? I'm not game to try those though. I want my car to feel the same left as it is right you know? And not have more than 7 setups per car (Which a lot of you probably think is already a lot! Lol).

I guess your main issue is that your rear tires are overheating during acceleration in long corners?
In this case, raise the power ramp angle in your diff to get less locking effect. It's possible that this will decrease your overall performance though.

FlexibleFelix
02-11-2017, 10:27
Lots of quotes! And lots of suggestions!

Ok here we go!

Opening rear brake ducts - I did try this, had almost no effect on the tires themselves, it just lowered the effectiveness of the rear brakes making me oversteer less. I know that doesn't sound right, so to clarify I normally run really low brake pressure (50% - 65%. Yes, that low) so I can trail brake corners really well. I lose some initial braking power, but I make up for it later. I could maybe say that the low pressure might be somehow related to heating up the tires more than if I went with a high pressure? Not related to the specific scrubbing case, but could maybe help me myself. Something to consider for sure. :)

Raising rear ride height - If there's anything I tried the most, it was this for sure. From memory, it only improved the stability a little bit. I normally tune with the cars running really high from the get go, but I went all over the place on the height in this Porsche.
In the end I went for a somewhat mid-range ride height, closer to the stable setup default but with a slightly lower front height if I recall correctly - haven't driven it in a while but I can double check if you like. It was either mid-range or it may have been closer to max ride height.

Stiffer rear suspension - as I said in the OP, I stiffened everything I could, to the point where it was basically maxed top to bottom. Nothing helped. Stiffening rear suspension helped it swing a bit more, and I tried to increase the oversteer effect by putting the rear ARB's up high enough so that it would swing out. I believe I put it a couple clicks away from max later though, as the car felt more stable. My goal was to also add toe-out to the rear, and make the car a little loose off power, so the back end would swing out and do so very comfortably so the tires wouldn't be stressed as easily. I didn't succeed tho.

Riding on the bump stops - I ended up with 2 mm front and back, since it felt pretty comfortable on them with all the extra expansion length for the suspension to play with. I went all over the place with these too, since I am sort of new to bump stops, took me some time to learn them. If you know any more about their effects on the car I'd love to know. :)

Generally speaking, as long as the Porsche tune I ended up with doesn't experience those hard bumps, dips, and/or lots of complex corners (e.g rising, off-camber to crests tend to be very stressing on the tires), it manages the heat fine, actually really well. It's just those circumstances, particularly the bumps and dips causing the rear outer tire to unsettle in a steady state mid corner, that melt the tires. The affected tire(s) can rise in temperature really fast.

Running hards in the mid-range where it's too hot for softs - I actually have a tune adjusted for running hard slicks and it's fantastic. I haven't tried adjusting it to run cold though. Interesting suggestion. I'm definitely interested to try that. :D

Last of all!


I guess your main issue is that your rear tires are overheating during acceleration in long corners?
In this case, raise the power ramp angle in your diff to get less locking effect. It's possible that this will decrease your overall performance though.

It happens whether I'm off power, braking, accelerating. I played a lot with the diff especially. I found running a higher preload helped stabilise the car if I could then manipulate more oversteer from other parts of the car, which is how I landed on that setup I mentioned at the start, which only lasts 5 laps on cold tires (Hard slicks setup lasts what feels like forever on it's tires even at operating temperature lol). The preload was actually really useful to help me end up with at least something to walk away with.
Running higher ramp angles was actually really helpful from memory. It didn't solve the issue, but it did help manage it after the fact. Getting the performance out of it elsewhere also was easier to do than the opposite as well. I even went to a spool setup (Since I have a Panoz that runs really well with a spool in GT1) to see if that worked, but like you said, too much locking decreased my performance. The spool was a little too much lol.


Hope that sheds a little more light on what I did with the Porsche. Some of the things you mentioned I did with the Acura as well, same as with Keena's suggestions about damping, which did help and reduced the stress on the outer front tire and balanced it better across the tires on the outer side.

Doug914
02-11-2017, 10:39
Great Post, and yes we modelled these modern slicks exactly as they are in real life. Softs are rarely faster than Hards because with the rubber tech nowadays the fastest compound is the one that matches the heat conditions. That means unless it's really cold ambient temps, the Hards are the ones to use.
i will say we that we adjusted the Hard's lower temp sensitivity slighty for patch 3, so there will be a bit more grip at low temps, so this might close up your gap you are experiencing between the softs and hards allowing the hards to be more widely usable. Most of the info for this came directly from the real drivers and the manufacturers themselves. Yes, The main heat build in the tires is slip or scrub (so "work" based). Another thing to be aware of is that the telemetries are showing bulk tread temps and not "flash" surface temps, which range 20-30C deg higher, but are difficult to work with for how rapidly they change.
For the specific problem of the 991R tires leaving the track, this is classic bumpstop contact being too aggressive. I'm not a big fan of bumpstops in real life chassis setup and also in virtual setups. So the first thing i would do is completly remove all the bumpstops. If that seems to have a positive effect on the problem, then slowly work them back up till you get a good compromise. Good luck :)

EDIT: Another item is too much diff lock in either direction, depending on if you are on or off the throttle at that point. My goto would usually be the decell side being too tight.

z3r0cool77
02-11-2017, 10:52
Or just reduce the grid to 15 total cars. Tire overheating is a known issue with over 15 cars on xbox one. I’ve yet to see a single car with over heating issues using default setups with a small grid.

Zaskarspants
02-11-2017, 11:19
Or just reduce the grid to 15 total cars. Tire overheating is a known issue with over 15 cars on xbox one. I’ve yet to see a single car with over heating issues using default setups with a small grid.

This is my experience too.

FlexibleFelix
02-11-2017, 11:25
Great Post, and yes we modelled these modern slicks exactly as they are in real life. Softs are rarely faster than Hards because with the rubber tech nowadays the fastest compound is the one that matches the heat conditions. That means unless it's really cold ambient temps, the Hards are the ones to use.
i will say we that we adjusted the Hard's lower temp sensitivity slighty for patch 3, so there will be a bit more grip at low temps, so this might close up your gap you are experiencing between the softs and hards allowing the hards to be more widely usable. Most of the info for this came directly from the real drivers and the manufacturers themselves. Yes, The main heat build in the tires is slip or scrub (so "work" based). Another thing to be aware of is that the telemetries are showing bulk tread temps and not "flash" surface temps, which range 20-30C deg higher, but are difficult to work with for how rapidly they change.
For the specific problem of the 991R tires leaving the track, this is classic bumpstop contact being too aggressive. I'm not a big fan of bumpstops in real life chassis setup and also in virtual setups. So the first thing i would do is completly remove all the bumpstops. If that seems to have a positive effect on the problem, then slowly work them back up till you get a good compromise. Good luck :)

EDIT: Another item is too much diff lock in either direction, depending on if you are on or off the throttle at that point. My goto would usually be the decell side being too tight.


Thanks!

I noticed in telemetry since getting the game that, for instance if you spin out while locking the brakes, then return to the track and you drive really slow (Like 1-5 kph/1-3 mph) the telemetry seems to show the heat changing and displaying repeats of different numbers across the tire, hotter, colder, etc. Could this be some display of the flash heat? Or am I way off the mark? :P

If I recall specifically with bump stops, I think I went as high as possible, and as low as 1 mm on the bump stops. Like I said earlier I'm still fairly new to these. I have experimented with it a lot on this car, but I can't remember if I tried 0 mm. Big difference between 1 mm & 0 mm?

I also did figure the diff locking rather awkwardly could've been a cause, but I'm sure I tried just about every angle.

Not to say this car isn't capable of not overheating. I can run the 'stable' setup without overheating as easily, but I can't run that setup fast at all. I'd take my Acura over it in that case.



Or just reduce the grid to 15 total cars. Tire overheating is a known issue with over 15 cars on xbox one. I’ve yet to see a single car with over heating issues using default setups with a small grid.


I did not experiment this with 15 other cars. I ran a lot of online practice sessions at about an hour each, but never got a full lobby. Any time I raced it or ran it in time trial, the fact that the race-warmers pre-heated my tires basically set me up for disaster within the same lap. Just about the whole time was spent in either, practice, qualifying or private testing. EDIT: Or Time Trial. I've yet to try single player.

However, as I said above and you've said too, the default setup can manage the heat much better when I run it. It's also much slower in my hands, probably why it's not overheating. :P

I find the 'Stable' setup to actually be a little bit of a mystery through all of it. Several times, I wiped everything clean and started from that setup to try and get the pace out of it without compromising it's heat management on the tires, none of it worked. Very nice to hear the hard slicks will be adjusted to close that somewhat grey area between compounds though (I've noticed it on other GT3 cars as well). Looking forward to that!

Sampo
02-11-2017, 12:38
I noticed in telemetry since getting the game that, for instance if you spin out while locking the brakes, then return to the track and you drive really slow (Like 1-5 kph/1-3 mph) the telemetry seems to show the heat changing and displaying repeats of different numbers across the tire, hotter, colder, etc. Could this be some display of the flash heat? Or am I way off the mark? :P


I think that's the flat spot you got when you locked your brakes.

honespc
02-11-2017, 12:54
I'm not a big fan of bumpstops in real life chassis setup and also in virtual setups. So the first thing i would do is completly remove all the bumpstops. If that seems to have a positive effect on the problem, then slowly work them back up till you get a good compromise. Good luck :)How do we remove bumstops completely?, in most cars you are not allowed to go lower than, for instance the 10 mark

FlexibleFelix
02-11-2017, 12:56
I think that's the flat spot you got when you locked your brakes.


Is that what it's called? Didn't know that. Was worth trying to guess though haha. Now I've learnt something new. :)

Mahjik
02-11-2017, 14:13
Also keep in mind that the Porsche will be more rear heavy compared to the other GT3's. With that, it's going to struggle with rear tire temps more than the other GT3's.

Lars Rosenquist
02-11-2017, 14:31
Is that what it's called? Didn't know that. Was worth trying to guess though haha. Now I've learnt something new. :)

Yes, the tire is divided into different segments with their own properties. The UI shows only the data for the one (inside/center/outside) on-track. So if one is colder/hotter due to circumstances then you will see the values change as the wheels rotate. :)

AOD_ZedZedski
02-11-2017, 14:33
TL;DR

I personally haven't found an issue with tires overheating yet. The only cars that I've been driving and heavily tuning were GT3 cars. Mostly: Ferrari 488 and Audi R8.
I find that Ferrari 488 handles better with Hard Slicks even on cold track with lowest tire pressure possible. As for running that car on hot track, it handles well with Hard Slicks at tire pressure in tuning setup somewhere between 1.38 - 1.45. Also, tires don't overheat.


So, next car that I've been testing in various conditions was Audi R8 LMS GT3. This car is a bit interesting as it actually handles much better on cold tires (like 40C - 60C) rather than on warm tires 90C - 105C. The Ferrari 488 obviously doesn't like these tire temps and needs to have somewhere 90C - 105C. I find this really strange. With that said, on Audi it seems that Slick Soft work well in condition when track temp is 30C and below, while Hard Slick work well above 30C. As for tire pressure in Tuning setup it ranges from 1.30 - 1.40. Anything more will make the car twitchy.

With this in mind, I did not have any tire overheating issue. So, I guess the overheating issue is driving style and actual car setup. As OP mentioned, friction is what will cause a huge tire temp increase but since I run my own setup that has more oversteering rather than understeering and I take corners smooth then I don't have this issue. Sometimes, I'm actually looking for a way to increase tire temperature since my tires are not heating enough even though I'm pushing WR lap times during the race.

FlexibleFelix
02-11-2017, 16:49
Also keep in mind that the Porsche will be more rear heavy compared to the other GT3's. With that, it's going to struggle with rear tire temps more than the other GT3's.

Absolutely! This is partially why I picked the Acura, since I knew it was anything but that. :P


TL;DR

I personally haven't found an issue with tires overheating yet. The only cars that I've been driving and heavily tuning were GT3 cars. Mostly: Ferrari 488 and Audi R8.
I find that Ferrari 488 handles better with Hard Slicks even on cold track with lowest tire pressure possible. As for running that car on hot track, it handles well with Hard Slicks at tire pressure in tuning setup somewhere between 1.38 - 1.45. Also, tires don't overheat.


So, next car that I've been testing in various conditions was Audi R8 LMS GT3. This car is a bit interesting as it actually handles much better on cold tires (like 40C - 60C) rather than on warm tires 90C - 105C. The Ferrari 488 obviously doesn't like these tire temps and needs to have somewhere 90C - 105C. I find this really strange. With that said, on Audi it seems that Slick Soft work well in condition when track temp is 30C and below, while Hard Slick work well above 30C. As for tire pressure in Tuning setup it ranges from 1.30 - 1.40. Anything more will make the car twitchy.

With this in mind, I did not have any tire overheating issue. So, I guess the overheating issue is driving style and actual car setup. As OP mentioned, friction is what will cause a huge tire temp increase but since I run my own setup that has more oversteering rather than understeering and I take corners smooth then I don't have this issue. Sometimes, I'm actually looking for a way to increase tire temperature since my tires are not heating enough even though I'm pushing WR lap times during the race.

To further provide some shorter detail on this for you - the Audi will feel better on soft slicks at lower temps. As I've said for the Porsche as well in the OP, and input from a dev above, it's very 1 to 1 with real life. If you can read up a little on the thread link I hunted down in the second post (Not sure if I can post links yet, but the thread trail is there.) there's more light on specific 'Ideals' for operating tire temperatures. Hard slicks prefer hotter tracks typically, while softs prefer colder, with their ideal performance regularly showing up at temperatures in the same fashion (100 degrees Celsius roughly for hards, 85 degrees Celsius or so for softs). I would agree with you that there is a vague cutoff somewhere (I figured it to be 29 degrees Celsius for hards, until recently. Will explain..) but it doesn't always speak the truth to track temperatures, or I guess, track temperatures combined with tire stress over each lap. There are outliers. Some obvious, some aren't.

For example, Monza. I've found running that track in the middle of summer (I believe the temperature is 38 degrees Celsius) around the middle of the day, clear weather, softs handle it. The heat probably is doing something, but anything from the track surface, to maybe the fact that most of Monza is spent running down straights between technical sections, could be why GT3's can tolerate it really easily. Another one is Le Mans, same scenario, more extreme use of straight lines...lol.

The 488 I've seen to be excellent at managing the heat. I can't seem to drive it quick though, despite having a good tune for it. Tires overheating does seem to be influenced by driving style from what I can tell. I'm not much when it comes to smooth steering versus others (Especially since I run a controller).

EDIT: I'm gonna head off for now. Thanks for the positive feedback all! I really appreciate it after all the effort! :D

AOD_ZedZedski
02-11-2017, 17:09
To further provide some shorter detail on this for you - the Audi will feel better on soft slicks at lower temps.




Yes, but my point was that Audi handles better when tire temperatures are actually cold and best temps are between 40C - 60C, which if you do the same for Ferrari then Ferrari gets a lot of understeering and oversteering with those tire temps. So for Ferrari ideal temps are between 90C - 105C, while for Audi, 90C - 105C is way too hot even though it is considered to be normal temperature. And it does not matter Soft or Hards for Audi at those temperatures.

Moreover, I find that Ferrari doesn't like Softs at all. No matter what conditions.

Obviously there is a need for more testing but there is something not right with consistency here.

Maybe it is different on Xbox but at least those are my observations on PC.

peterCars
04-11-2017, 02:05
the telemetry HUD has the brakes on it. I am watching that one closely now whilst tuning the Fanatec pedal setting for brakes.

Goruk
07-11-2017, 16:00
Great Post, and yes we modelled these modern slicks exactly as they are in real life. Softs are rarely faster than Hards because with the rubber tech nowadays the fastest compound is the one that matches the heat conditions. That means unless it's really cold ambient temps, the Hards are the ones to use.
i will say we that we adjusted the Hard's lower temp sensitivity slighty for patch 3, so there will be a bit more grip at low temps, so this might close up your gap you are experiencing between the softs and hards allowing the hards to be more widely usable. Most of the info for this came directly from the real drivers and the manufacturers themselves. Yes, The main heat build in the tires is slip or scrub (so "work" based). Another thing to be aware of is that the telemetries are showing bulk tread temps and not "flash" surface temps, which range 20-30C deg higher, but are difficult to work with for how rapidly they change.
For the specific problem of the 991R tires leaving the track, this is classic bumpstop contact being too aggressive. I'm not a big fan of bumpstops in real life chassis setup and also in virtual setups. So the first thing i would do is completly remove all the bumpstops. If that seems to have a positive effect on the problem, then slowly work them back up till you get a good compromise. Good luck :)

EDIT: Another item is too much diff lock in either direction, depending on if you are on or off the throttle at that point. My goto would usually be the decell side being too tight.

How cold is cold?

Bealdor
07-11-2017, 16:43
How cold is cold?

<15C roughly