Car Behavior and Tire Temps after Patch 2.0PS4

[Jack Dulmage]

It doesn't matter at all, but these findings are inconsistent with the results I get at Daytona Road Course, Long Beach and Laguna Seca in the Huracan GT3.

If I need to increase Temp in a tire, I increase the Pressure in it. But the first goal for me is to ensure the Tire is up to the correct Pressure. You can have an under Pressured tire that gets hot, but performance is so poor is it silly to do so and it eventually gets cold again. For me the key has been getting the Pressure in the correct range and making small incremental Pressure changes to influence Temps. If my Right Front is too cold at Long Beach, I increase the Pressure. If the Left Rear is too hot at Long Beach, I decrease the Pressure. This has worked well for me.

And I'm sure driving style does play a part, and id like to make it clear that i am not saying that decreasing pressure is a cure all, and asymmetrical pressures are obviously the best way to get optimal pressures and heat for each track. However, looking at the physics behind real life optimal tire temperature and pressure, it is usually a safe bet that if the tires do not heat heat up after significant lateral force is put into them over the course of 3-5 laps, pressures are most likely to high. This is based on the knowledge that a softer tire produces more energy per square inch of the contact patch on lateral inertial movements due to the increased tire flex and sidewall deformation. This obviously depends on suspension set up as well (camber, toe, roll, etc) but in general, this seems to be the strategy used after suspension etc. has been tuned, as tire pressure should be the last resort. This is what i have experienced in Pcars 2, that after i have exhausted my resources through the tuning of suspension etc, i still cannot get optimal temperature gradients in the tires, although lowering the pressure does seem to get closer to the optimal value (depending on track, weather, compound).

Perhaps i misunderstand what you are saying your experience is? Maybe a video showing how your tires interact with pressure differentials or screenshots? Preferably at Long Beach in a GT3 car as this is a track where i experienced a lack of tire heat regardless of pressures.

I also looked more closely at the document (Michelin) posed by @F1Racer68 and realized that it is from the early 2000's i believe? They were still using the Audi R8 LMP900 as their top benchmark LMP car... Through further research, it appears that this data is severely outdated and the new compounds are run at higher temperatures, however i could not find any updated Michelin data that was as detailed... Most of the research data ii could source was from teams, interviews with manufacturer representatives and expert analysis, nothing of any statistical weight unfortunately.

Sorry for the long post,

Let me know if there is anything i need to go further into/needs to be sourced!

 

[Wayne Kerr]

Has anyone even given the thought that for a given pressure window (ie a RANGE) that the tire works well at, you run different pressures on different corners on the car at different venues depending on which tire gets loaded the most?

It's not like "32 psi is optimal pressure" so you run 32 regardless if it's long beach or wgi.

 

[Wayne Kerr]

This is based on the knowledge that a softer tire produces more energy per square inch of the contact patch on lateral inertial movements due to the increased tire flex and sidewall deformation.

From a pure physics / mathematics stand point for a tire, energy is the integral of the power "generated" by the tire with respect to time. Unless the force produced by the tire at a given velocity is known, in the real world one cannot definitively claim a softer tire produces more energy per sq inch of contact patch.

 

[ozwheels]

Has anyone even given the thought that for a given pressure window (ie a RANGE) that the tire works well at, you run different pressures on different corners on the car at different venues depending on which tire gets loaded the most?

It's not like "32 psi is optimal pressure" so you run 32 regardless if it's long beach or wgi.

I’m not sure what you’re saying here. Are you saying run different pressures at different tracks? Such as lower for tight technical tracks and higher for high speed tracks.

 

[Jack Dulmage]

From a pure physics / mathematics stand point for a tire, energy is the integral of the power "generated" by the tire with respect to time. Unless the force produced by the tire at a given velocity is known, in the real world one cannot definitively claim a softer tire produces more energy per sq inch of contact patch.

Not really sure i follow? Lateral force put through a tire does create more friction/thermal energy, with more tire flex and larger contact patch (achieved through a softer tire) should lead to higher energy coefficients and higher temperature...? Maybe my physics are off... but that's what i always understood and have read...

 

[Wayne Kerr]

I’m not sure what you’re saying here. Are you saying run different pressures at different tracks? Such as lower for tight technical tracks and higher for high speed tracks.

That's exactly what I'm saying.

Not really sure i follow? Lateral force put through a tire does create more friction/thermal energy, with more tire flex and larger contact patch (achieved through a softer tire) should lead to higher energy coefficients and higher temperature...? Maybe my physics are off... but that's what i always understood and have read...

What I'm trying to say is this: Let's say you take 100R at fuji for example. Keeping everything about the car as the same, how do you know what the latG at that corner is for a tire running at 1.9bar vs that of a tire at 2.4 bar? W/o the latG, how does one find the "energy" And w/o data aq, how does one know what the latG is? One won't know the energy until at the very least that is found. Nevermind the trade off between the lat G difference vs the shoulder stress difference.

But then again all of this is just a circle jerk discussion for the sake of circle jerking. For all intents and purposes in the game, just run the \ pressure that gives you either a) the best single lap lap time, or b) most consistent race stint lap time. It isn't that difficult.

 

[ozwheels]

That's exactly what I'm saying.



What I'm trying to say is this: Let's say you take 100R at fuji for example. Keeping everything about the car as the same, how do you know what the latG at that corner is for a tire running at 1.9bar vs that of a tire at 2.4 bar? W/o the latG, how does one find the "energy" And w/o data aq, how does one know what the latG is? One won't know the energy until at the very least that is found. Nevermind the trade off between the lat G difference vs the shoulder stress difference.

But then again all of this is just a circle jerk discussion for the sake of circle jerking. For all intents and purposes in the game, just run the \ pressure that gives you either a) the best single lap lap time, or b) most consistent race stint lap time. It isn't that difficult.

I understand what your saying. I think Jack means energy in the sense of lateral force vs slip angle generating heat through higher slip rather than a literal energy reference. As you said though without data it’s purley a feel thing in games.

 

[Jack Dulmage]

That's exactly what I'm saying.



What I'm trying to say is this: Let's say you take 100R at fuji for example. Keeping everything about the car as the same, how do you know what the latG at that corner is for a tire running at 1.9bar vs that of a tire at 2.4 bar? W/o the latG, how does one find the "energy" And w/o data aq, how does one know what the latG is? One won't know the energy until at the very least that is found. Nevermind the trade off between the lat G difference vs the shoulder stress difference.

But then again all of this is just a circle jerk discussion for the sake of circle jerking. For all intents and purposes in the game, just run the \ pressure that gives you either a) the best single lap lap time, or b) most consistent race stint lap time. It isn't that difficult.

This is the issue, the tire pressures min/max do not allow me to get accurate tire temperature compared to real life data. Not that the minimum should be decreased, as 18 PSI starting is pretty low, but rather how this pressure effects the tire temperature seems to be too cold compared to real life data. This is mostly speculation as i am not a Pro racing driver and perhaps they are able to put more force in the tire on a given lap then i am, but there is no reason that i should be dropping the pressures to the minimum for most tracks on the Hard compound, unless they do this in real life, but i am somewhat doubting this? Also, maybe i am missing something? Some setting or piece of data that i have overlooked and this is why my cars tires will not heat up adequately. If it be that i dont drive the car "hard enough", i race my career mode with the AI at 115 and aggression at 70-75, and i believe these lap times are fast enough? Daytona i ran 1:45's in qually and tires were just at the low end of being hot enough on soft tires.

I understand what your saying. I think Jack means energy in the sense of lateral force vs slip angle generating heat through higher slip rather than a literal energy reference. As you said though without data it’s purley a feel thing in games.

Yes exactly.

 

[crowhop]

In NASCAR they run the absolute lowest possible Pressure, especially in the rear tires (and even less in the Right Rear) at a track like Martinsville vs when they'd run very high Pressure, especially on the Right side, at the larger Ovals.

I discovered most of what I know simply from running laps at Daytona Road Course. When I first got the game, assuming tuning temps and pressures would match the first title, I assumed you combat low temps with low pressure and vice versa. But at Daytona Road Course, that simply doesn't work. The Default Pressure didn't get the tires hot, so I dropped them further. That only served to make the tires colder or stay largely the same. And they gripped even less.

I didn't know why it worked the way it does until I read @F1Racer68's post and talked to @Wayne Kerr. I just knew raising the Pressures can raise the temps.

 

[chopz]

I didn't know why it worked the way it does until I read @F1Racer68's post and talked to @Wayne Kerr. I just knew raising the Pressures can raise the temps.

More pressure could very well mean less contact patch from reduced pliability which would result in increased tire spin or slide, which is why a person would see increased temperatures.

Ideally, we should be adjusting tire pressure, camber, and toe to achieve the greatest contact patch at load in the corner. This is however not easy to determine based on the data we are given to assess the situation. The only tool we are given is the three three tire temperatures per tire and feeling of oversteer/understeer. From there we adjust camber, toe, suspension for desired results.

There is no such thing as the 'proper' pressure for a class of car as this is always dependent on the rest of the car setup and individual track. The proper pressure is the pressure that begets the greatest contact patch at load in the corner at the desirable temperature to produce the most grip.

 

[gladbecker82]

Xbox here. Basically oval racing is impossible now due this bug and yes its not "realism" to have smoking tires in a indycar in a oval unless you do Donuts after victory. And that goes for every high speed corner in the game in all cars from street to prototypes.

This has to be fixed asap as that is actually something that wasnt such a big issue prior to 2.0. now its worse

 

[crowhop]

More pressure could very well mean less contact patch from reduced pliability which would result in increased tire spin or slide, which is why a person would see increased temperatures.

Ideally, we should be adjusting tire pressure, camber, and toe to achieve the greatest contact patch at load in the corner. This is however not easy to determine based on the data we are given to assess the situation. The only tool we are given is the three three tire temperatures per tire and feeling of oversteer/understeer. From there we adjust camber, toe, suspension for desired results.

There is no such thing as the 'proper' pressure for a class of car as this is always dependent on the rest of the car setup and individual track. The proper pressure is the pressure that begets the greatest contact patch at load in the corner at the desirable temperature to produce the most grip.

Less pressure could very well mean too much roll in the sidewall resulting in increased tire spin or slide, which is why a person would see increased temperatures.

 

[Jack Dulmage]

In NASCAR they run the absolute lowest possible Pressure, especially in the rear tires (and even less in the Right Rear) at a track like Martinsville vs when they'd run very high Pressure, especially on the Right side, at the larger Ovals.

I discovered most of what I know simply from running laps at Daytona Road Course. When I first got the game, assuming tuning temps and pressures would match the first title, I assumed you combat low temps with low pressure and vice versa. But at Daytona Road Course, that simply doesn't work. The Default Pressure didn't get the tires hot, so I dropped them further. That only served to make the tires colder or stay largely the same. And they gripped even less.

I didn't know why it worked the way it does until I read @F1Racer68's post and talked to @Wayne Kerr. I just knew raising the Pressures can raise the temps.

I also tried increasing pressures... I went both ends of the spectrum, higher pressures did nothing for me except keep the tires cold and offer less grip... Lowering the pressures decreased the temp, but not enough. This may be based on our different driving styles, however i was setting 1:45's which felt fairly quick (not 100% sure what is quick in a GT3 car around here), putting a lot of lateral load into the tire especially during the first sector

 

[Wayne Kerr]

This is the issue, the tire pressures min/max do not allow me to get accurate tire temperature compared to real life data. Not that the minimum should be decreased, as 18 PSI starting is pretty low, but rather how this pressure effects the tire temperature seems to be too cold compared to real life data.

with air / nitrogen that was passed twice through an air dry system before being pumped into the tire, a 10-12 psi gain is absolutely within reason for a GT car.

the only "variable" with the amount of gain is the temperature of the air source before being pumped into the tire. TBH if one knows that temperature as well, one could get the hot pressure bang on, every time.

 

[Jack Dulmage]

with air / nitrogen that was passed twice through an air dry system before being pumped into the tire, a 10-12 psi gain is absolutely within reason for a GT car.

Agreed? I am saying 18 is appropriate.. i have nothing wrong with the minimum, only how it is effected.

 

[chopz]

Less pressure could very well mean too much roll in the sidewall resulting in increased tire spin or slide, which is why a person would see increased temperatures.

It could, you would know this is the case by significantly higher outside band temperature than the inside. My adjustments would then be stiffen the anti-roll and increase negative camber to see how the temperatures adjusted. Then I would adjust pressure for temperature as needed.

 

[ozwheels]

I’ve continued some testing at Fuji and the hard tires have very little wear. I mean almost zero. Pushing almost flat out lap after lap and they have constant maximum grip lap after lap even with temps reaching 210F.

 

[AllReD]

I haven't purchased the game as yet, but I have been following up on the topic of tire temps and pressure.

After watching this video I can certainly that I am now thoroughly confused.

His tire pressure is actually dropping throughout the race whilst his temps seem to be holding steady (based on color indicators). They then seem to level out at 20psi fronts and 16psi rear. The weather changes up a bit to hazy/cloudy but still his psi is holding.

I would think that it would be the opposite and that this tire pressure would climb as he starts the raise and then level out somewhat but still be higher than at the beginning.

Am I missing something obvious here?

 

[ozwheels]

I haven't purchased the game as yet, but I have been following up on the topic of tire temps and pressure.

After watching this video I can certainly that I am now thoroughly confused.

His tire pressure is actually dropping throughout the race whilst his temps seem to be holding steady (based on color indicators). They then seem to level out at 20psi fronts and 16psi rear. The weather changes up a bit to hazy/cloudy but still his psi is holding.

I would think that it would be the opposite and that this tire pressure would climb as he starts the raise and then level out somewhat but still be higher than at the beginning.

Am I missing something obvious here?

I’m pretty sure it’s the tire pressure bug that happens sometimes. I had the same thing in a GT3 race. Tires started at 28 PSI and dropped throughout the race while the temperature climbed. I’ve also had tires at 40 PSI after a pit stop. @twitcher posted about that bug in this thread also.

 

[chopz]

Here's another thing to try out in regards to bizarre tire behavior.

Start a private testing session, manual pit lane control, load whatever setup you want with whatever tires you want, hit the ready button, but do not do anything. Do not brake, accelerate, turn, nothing. Just sit there... and watch the PSI and temperature of the tires go up... o_O

 

[BrandonW77]

What pisses me off is that it shows in Bars in the tuning menu and PSI in the HUD. I have no concept of what a "Bar" is so when I try to adjust the pressures I have no idea of how big a change I'm making. And of course the HUD doesn't show temps either which makes it difficult to know what affect your changes are having.

 

[Jack Dulmage]

What pisses me off is that it shows in Bars in the tuning menu and PSI in the HUD. I have no concept of what a "Bar" is so when I try to adjust the pressures I have no idea of how big a change I'm making. And of course the HUD doesn't show temps either which makes it difficult to know what affect your changes are having.

This ^ ... I bought the simdash APP way back for PCARS1 and you can put BAR and PSI on the same page so it makes it easier as i can see the conversions live and just make changes like that... made it easier i found! I agree though, surprised it isn't in kilopascal for the metric setting

 

[BrandonW77]

This ^ ... I bought the simdash APP way back for PCARS1 and you can put BAR and PSI on the same page so it makes it easier as i can see the conversions live and just make changes like that... made it easier i found! I agree though, surprised it isn't in kilopascal for the metric setting

I was using DashMeterPro on a tablet which at least showed me PSI and temps on the tires but I just went VR so now I have to rely on what the HUD provides. Kinda bizarre they don't include temps on the HUD.

 

[Wayne Kerr]

1 dozen eggs

12 eggs

tomato tomahhhhto

 

[Jack Dulmage]

I was using DashMeterPro on a tablet which at least showed me PSI and temps on the tires but I just went VR so now I have to rely on what the HUD provides. Kinda bizarre they don't include temps on the HUD.

Hard to feel sorry for you... wish i had that problem haha

 

[fasj6418]

Well, doing a hotlap challenge in Neogaf with the F3.5 i´ve found that some of the "optimal" pressures are just flat out wrong, at least for hotlapping.

Maybe it changes over the course of a looong race, but not so much for 4-5 lap stints.

I ended up setting the WR for the car with 0.90/0.70 pressures on the tires, it felt a lot better, more predictable and under control. Of course you have to tune the suspension to go with it, but that´s expected.

It´s like in Nascar and so many other series that we keep hearing, you run as low as you can, most of the times not following the recommended tire pressures from the manufacturers.

You can also run maximum camber to get better results, at least for a few laps there´s no trade off.

Considering most of the online races are at best 10 laps, i think we can be very aggressive with the setups, and for hotlapping in a no brainer.

Testing the F3.5 with the recommended pressures felt like a chore, the car would behave horribly and it was also significantly slower.

Testing was at Donington National, on PC.

 

[ozwheels]

Well, doing a hotlap challenge in Neogaf with the F3.5 i´ve found that some of the "optimal" pressures are just flat out wrong, at least for hotlapping.

Maybe it changes over the course of a looong race, but not so much for 4-5 lap stints.

I ended up setting the WR for the car with 0.90/0.70 pressures on the tires, it felt a lot better, more predictable and under control. Of course you have to tune the suspension to go with it, but that´s expected.

It´s like in Nascar and so many other series that we keep hearing, you run as low as you can, most of the times not following the recommended tire pressures from the manufacturers.

You can also run maximum camber to get better results, at least for a few laps there´s no trade off.

Considering most of the online races are at best 10 laps, i think we can be very aggressive with the setups, and for hotlapping in a no brainer.

Testing the F3.5 with the recommended pressures felt like a chore, the car would behave horribly and it was also significantly slower.

Testing was at Donington National, on PC.

What is the recommended pressure for that car?

Max camber has been quicker for me in GT3 cars as well.

 

[fasj6418]

What is the recommended pressure for that car?

Max camber has been quicker for me in GT3 cars as well.

1.70/1.55 was the number used in the official forums, so my setup was drastically different.

It´s all good thou, i believe you can set up a car to go fast in with different approaches, so the only thing that´s clear is that tuning is complex and full of possibilities.

 

[ozwheels]

1.70/1.55 was the number used in the official forums, so my setup was drastically different.

It´s all good thou, i believe you can set up a car to go fast in with different approaches, so the only thing that´s clear is that tuning is complex and full of possibilities.

That’s an 11 psi difference lol.

 

[BrandonW77]

Hard to feel sorry for you... wish i had that problem haha

I'm making do.