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wings596
16-03-2018, 14:11
Another Rookie question from me!

I've found (I think ...) a set of controller settings (for One X) I can use, and following exploratory offline races against the (fairly low settings) AI in a Honda Type R and a career start in a Ginetta, I've moved on to GT4 races in a Cayman ... the rapid rate of tyre wear in this car - if it's that - is puzzling me.

In repeated 10 lap races, tyres and brakes need fully warming in lap 1, are fine for laps 2 - 7, and from 8 the tyres seem to start to go off? Which seems a bit quick? Tyres and brakes look OK on the telemetry, but braking and grip both seem to go off for the last 2 - 3 laps ...

Not sure if:
- I'm imagining this, still not being 100% with the controller handling?

- It's happening for real, and meant to be because the tyres last only for 7 laps on a Cayman (I'm positively trying not to flat spot / scuff them ... icons show virtually no wear), but this seems too short a life?

- It's happening, but as a sort of "pro rata" effect: i.e. I cannot escape tyre degradation effects by choosing a short, 10 laps, race, because the last quarter (?) of any race is subject to some sort of "wear penalty", which is incurred irrespective of the actual number of laps?

There was a similar sort of effect for the Type R, but not nearly as marked and at the time I thought it was just my driving! (Which it may well be, of course!)

Any insights gratefully received ...

Atak Kat
16-03-2018, 14:20
By chance....
Is the track temps high (like 35-40+)?
And are you using softs?

CSL-Drive
16-03-2018, 14:26
Which track/tire/weather

What is the precentage of tire wear. 75%? Yeah you lose time then. But 3 laps is maybe not worth pitting.

Also it is possible that the race was manually set to amplify tire wear, which is possible online, maybe career too.

Or a weather that is synced to the race, maybe allot of wind blows dust on the track.

wings596
16-03-2018, 19:23
By chance....
Is the track temps high (like 35-40+)?
And are you using softs?

The track temps were high ... tyres were auto selection, I sure (I think!) were hard slicks ... at those high temps, would the tyres last only 7 (or so) laps?

Thanks for the ideas.

wings596
16-03-2018, 19:25
Which track/tire/weather

What is the precentage of tire wear. 75%? Yeah you lose time then. But 3 laps is maybe not worth pitting.

Also it is possible that the race was manually set to amplify tire wear, which is possible online, maybe career too.

Or a weather that is synced to the race, maybe allot of wind blows dust on the track.

Track was Monza, and yes temps were high.

Tyre wear? According to the on screen icons, wear was minimal, hardly visible.

I didn't know that races could be set manually to amplify tyre wear? That can be done? How?

Thanks for the ideas.

g.stew
16-03-2018, 19:43
I used to notice the same thing on the last laps of career races but I put it down to me being under more pressure and losing focus. I really have to remind myself (or Crew Chief does) to focus on braking points, etc towards the end of a race.

One thing you could try is adjusting the length of the race in career. I'm not sure if that class is timed or # of laps, but try it a couple of times with different race length. You can do restart session if you finish the race, and then immediately exit and then adjust the length and start it again. See if you are seeing the same behavior at the same point of the race (ie. last 1/3 or whatever) regardless of the race length.

Have you tried using a 3rd party telemetry app to record your race telemetry? I'm on xbox too and I'm using vrHive. You could then go back at the end and walk through each lap and see what exactly is changing from lap to lap. You would be able to see there if your tire wear was increasing or something else was going on. You can compare 3 laps against each other with the telemetry graphs and see if anything is difference. This is how I realized that my braking was getting very inconsistent after a couple of laps which just led to other problems.

Bealdor
16-03-2018, 19:52
Track was Monza, and yes temps were high.

Tyre wear? According to the on screen icons, wear was minimal, hardly visible.

I didn't know that races could be set manually to amplify tyre wear? That can be done? How?

Thanks for the ideas.

Sounds like too high tire pressures to me (yes they do need more than 3 laps to stabilise).
Either reduce pressures or open your brake ducts more.
What pressures did the telemetry HUD show you after those 7 laps?

Atak Kat
16-03-2018, 19:54
Maybe hkraft300 will reply here. He has some similar observations as I do regarding the tire degradation.

There seems to be a way that the tires surface can get cooked and less effective even if it does not really show it in the telemetry. It seems (to me) that you can ruin the tire grip by pushing them too hard, locking the brakes, etc, even if it doesn't show in the telemetry of the tire life. I have experienced it when I have locked up too much, or had spins. It's almost as if you are ruining the tire surface, but it is not the same as tire life. I have seen it most often with the rears, where I push too much, and then I find that the rears just lose grip and I tend to spin in corners where previously I had no problem.

If the auto selection chose the soft tires, then it does seem similar to what I have seen. In my experience so far, soft tires, higher temps, can last about 8-10 good laps if you are pushing hard. Then, they go off a bit, or maybe said differently, the tire surface seems to loose some effectiveness. The tire life shown in telemetry seems to be different, and maybe is measuring a different thing. They still last, but not to the same degree of grip that the were for the earlier laps.

Maybe I'm missing something too. But this is what I've experienced.

wings596
16-03-2018, 20:11
I used to notice the same thing on the last laps of career races but I put it down to me being under more pressure and losing focus. I really have to remind myself (or Crew Chief does) to focus on braking points, etc towards the end of a race.

One thing you could try is adjusting the length of the race in career. I'm not sure if that class is timed or # of laps, but try it a couple of times with different race length. You can do restart session if you finish the race, and then immediately exit and then adjust the length and start it again. See if you are seeing the same behavior at the same point of the race (ie. last 1/3 or whatever) regardless of the race length.

Have you tried using a 3rd party telemetry app to record your race telemetry? I'm on xbox too and I'm using vrHive. You could then go back at the end and walk through each lap and see what exactly is changing from lap to lap. You would be able to see there if your tire wear was increasing or something else was going on. You can compare 3 laps against each other with the telemetry graphs and see if anything is difference. This is how I realized that my braking was getting very inconsistent after a couple of laps which just led to other problems.

Yep, I realised as I was posting that I had kept to the same race lengths, and could try 6 and 12/15 laps and see if the degradation was a % of the race length or an absolute number of laps ... I'll try that!

The telemetry app sounds good ... any guidance on setting it up and running it with an X Box (One X) set up would be appreciated.

wings596
16-03-2018, 20:13
Sounds like too high tire pressures to me (yes they do need more than 3 laps to stabilise).
Either reduce pressures or open your brake ducts more.
What pressures did the telemetry HUD show you after those 7 laps?

The tuning was all left as default stable set up ... cannot now recall precise telemetry pressures, but they - and temperatures - did not strike me at the time as excessive. I'll try it again and pay more precise attention this time!

Thanks

Bealdor
16-03-2018, 20:14
Yep, I realised as I was posting that I had kept to the same race lengths, and could try 6 and 12/15 laps and see if the degradation was a % of the race length or an absolute number of laps ... I'll try that!

The telemetry app sounds good ... any guidance on setting it up and running it with an X Box (One X) set up would be appreciated.

Tire wear is not scaled by race length. It's not scripted.

Keena
16-03-2018, 20:14
Maybe hkraft300 will reply here. He has some similar observations as I do regarding the tire degradation.

There seems to be a way that the tires surface can get cooked and less effective even if it does not really show it in the telemetry. It seems (to me) that you can ruin the tire grip by pushing them too hard, locking the brakes, etc, even if it doesn't show in the telemetry of the tire life. I have experienced it when I have locked up too much, or had spins. It's almost as if you are ruining the tire surface, but it is not the same as tire life. I have seen it most often with the rears, where I push too much, and then I find that the rears just lose grip and I tend to spin in corners where previously I had no problem.

If the auto selection chose the soft tires, then it does seem similar to what I have seen. In my experience so far, soft tires, higher temps, can last about 8-10 good laps if you are pushing hard. Then, they go off a bit, or maybe said differently, the tire surface seems to loose some effectiveness. The tire life shown in telemetry seems to be different, and maybe is measuring a different thing. They still last, but not to the same degree of grip that the were for the earlier laps.

Maybe I'm missing something too. But this is what I've experienced.

You may be experiencing something known as Reverted Rubber Aquaplaning. Reverted rubber aquaplaning occurs when the heat of friction from a locked wheel in contact with the surface causes the rubber to revert to its un-cured state. Its most commonly associated with a film of water becoming trapped under the tyre, but the chemical process is applicable in all conditions, so the aquaplaning term is a bit of a misnomer. I have no idea if it is modelled in the sim, but the phenomena of tyres losing their chemical structure through thermal irregularities is well known. I'm pretty sure I experienced it today in my single player race after a monumental front lock up. Grip was seriously degraded for several corners after, despite a relatively minor thermal indication on the telemetry. Big kudos to SMS if they have this level of detail in the tyre model.

wings596
16-03-2018, 20:19
Tire wear is not scaled by race length. It's not scripted.

OK, thanks for the confirmation. I thought / expected that it was not ... but the issues seemed to arrive at almost exactly the same point in all of the "sample" races ...

I was pretty sure that my driving is not consistent enough to produce exactly the same tyre state at the same point after 7 laps of driving ... but perhaps it is after all!

Bealdor
16-03-2018, 20:22
OK, thanks for the confirmation. I thought / expected that it was not ... but the issues seemed to arrive at almost exactly the same point in all of the "sample" races ...

I was pretty sure that my driving is not consistent enough to produce exactly the same tyre state at the same point after 7 laps of driving ... but perhaps it is after all!

Tire pressure is very dependant of your brake temps, and it normally takes 5-6 laps for the pressures to stabilise, (almost) regardless of driving style.

wings596
16-03-2018, 20:24
You may be experiencing something known as Reverted Rubber Aquaplaning. Reverted rubber aquaplaning occurs when the heat of friction from a locked wheel in contact with the surface causes the rubber to revert to its un-cured state. Its most commonly associated with a film of water becoming trapped under the tyre, but the chemical process is applicable in all conditions, so the aquaplaning term is a bit of a misnomer. I have no idea if it is modelled in the sim, but the phenomena of tyres losing their chemical structure through thermal irregularities is well known. I'm pretty sure I experienced it today in my single player race after a monumental front lock up. Grip was seriously degraded for several corners after, despite a relatively minor thermal indication on the telemetry. Big kudos to SMS if they have this level of detail in the tyre model.

Interesting, thanks.

I would only add that, for me in these instances, the tyres are fine for 7 laps and then (seem to) "go" at the same point for the rest of the race ... so it doesn't seem like it's one big lockup etc. followed by a temporary degradation which then recovers.

g.stew
16-03-2018, 21:08
The telemetry app sounds good ... any guidance on setting it up and running it with an X Box (One X) set up would be appreciated.

The setup is pretty easy. Check the vrHive thread (http://forum.projectcarsgame.com/showthread.php?58222-PC-XB1-PS4-vrHive-Dashes-Telemetry-Live-Data-Arduino-Client-Server-more) for details in the first post. It has instructions and videos for xbox setup. It's basically just setting the udp setting in the game to pcars 1 udp and then starting the app and hitting connect. As long as your computer is on the same network then it shouldn't be a problem.

I just usually start mine running whenever I play so it's recording all my laps.

hkraft300
16-03-2018, 22:46
The tuning was all left as default stable set up ... cannot now recall precise telemetry pressures, but they - and temperatures - did not strike me at the time as excessive.

1.9 Bar hot pressure is excessive in GT cars. Prolonged >90c is excessive for soft tires. >700c peak is excessive for steel brakes. Since your tires aren’t worn I also suspect your tire pressures are too high.

The game has such a huge range of locations and weather that a little tuning is necessary for races 10+ laps. Below that, you can adapt/manage it to the flag.


You may be experiencing something known as Reverted Rubber Aquaplaning. Reverted rubber aquaplaning occurs when the heat of friction from a locked wheel in contact with the surface causes the rubber to revert to its un-cured state....

Don’t think it’s simulated that far but I know there’s several layers of temperature modelled from core to tire surface. From a big slide the surface can overheat and lose grip and it won’t show on telemetry unless/until that excess heat is maintained (by drifting, for example) and soaks through to the core. Manageable, just like if you’re on soft tires and suddenly the track gets hot, you can manage your pace to control tire temperature.

Atak Kat
17-03-2018, 04:33
I would only add that, for me in these instances, the tyres are fine for 7 laps and then (seem to) "go" at the same point for the rest of the race ... so it doesn't seem like it's one big lockup etc. followed by a temporary degradation which then recovers.

If you are softs, in hotter temps, then that sounds similar to what I experience. I think we are overheating the tires as hkraft300 describes, but it's not coming through (yet) on the temp readings in the hud. 7-10 laps into a hotter race, on softs, sounds about the same time I start to see them degrade, depending how I'm driving.

Can be partially managed by the way you drive. Better to dial it back a bit, rather than end up in a spin. In fact, once you spin once, I find that the tires do not come back to previous grip level. Even if you when you let them cool down.

wings596
17-03-2018, 08:11
The setup is pretty easy. Check the vrHive thread (http://forum.projectcarsgame.com/showthread.php?58222-PC-XB1-PS4-vrHive-Dashes-Telemetry-Live-Data-Arduino-Client-Server-more) for details in the first post. It has instructions and videos for xbox setup. It's basically just setting the udp setting in the game to pcars 1 udp and then starting the app and hitting connect. As long as your computer is on the same network then it shouldn't be a problem.

I just usually start mine running whenever I play so it's recording all my laps.

Thanks! I'll look into it.

EDIT: Ooops ... looks like it is PC only ... I run a Mac, and had just assumed it would support both PC and Mac, but with no Mac version (?) I cannot run it. Pity ...

wings596
17-03-2018, 08:13
1.9 Bar hot pressure is excessive in GT cars. Prolonged >90c is excessive for soft tires. >700c peak is excessive for steel brakes. Since your tires aren’t worn I also suspect your tire pressures are too high.

The game has such a huge range of locations and weather that a little tuning is necessary for races 10+ laps. Below that, you can adapt/manage it to the flag.



Don’t think it’s simulated that far but I know there’s several layers of temperature modelled from core to tire surface. From a big slide the surface can overheat and lose grip and it won’t show on telemetry unless/until that excess heat is maintained (by drifting, for example) and soaks through to the core. Manageable, just like if you’re on soft tires and suddenly the track gets hot, you can manage your pace to control tire temperature.

Very useful info, helpful, thanks.

wings596
17-03-2018, 08:16
If you are softs, in hotter temps, then that sounds similar to what I experience. I think we are overheating the tires as hkraft300 describes, but it's not coming through (yet) on the temp readings in the hud. 7-10 laps into a hotter race, on softs, sounds about the same time I start to see them degrade, depending how I'm driving.

Can be partially managed by the way you drive. Better to dial it back a bit, rather than end up in a spin. In fact, once you spin once, I find that the tires do not come back to previous grip level. Even if you when you let them cool down.

I will have to pay more attention to driving to manage the tyre temperatures ...