Project Cars 2 tire pressures

[Seb Weasel]

@IanBell , first of all thank you for all your work and participation here!
Now for the question. Could you please confirm something for many of us wondering in GT3 and LMP leagues I race in?
Here is Pirelli's Tire Data Booklet attached. In this they explain that the goal when setting up is precise hot pressures (and therefore temperature variation). It is what they call P. TARGET. Interestingly (for me!), target pressures can vary for left / right tires if running on an oval, and rear / front axle to account for weight distribution, but not on a per corner basis. So that would mean setting individual cold pressures to reach P. TARGET.
Even more fascinating (again for me ), if I understand correctly, camber is to be used as well to reach P. TARGET if necessary. I guess if tires go over P. TARGET even though they were set at P. MIN (minimum cold pressure), then camber is to be used to reach hot pressure target.
I read similar recommendations on a few different sources.
Is this how the model works in Project Cars 2, with hot pressure targets mentioned on the link below?
http://forum.projectcarsgame.com/showthread.php?57541-Project-CARS-2-Tyre-Temps

Neeeext brake temps! Haha.
Hopefully you or someone from the team can clear that out. We basically want to know were peak performance is.

 

[TexasTyme214]

@IanBell , first of all thank you for all your work and participation here!
Now for the question. Could you please confirm something for many of us wondering in GT3 and LMP leagues I race in?
Here is Pirelli's Tire Data Booklet attached. In this they explain that the goal when setting up is precise hot pressures (and therefore temperature variation). It is what they call P. TARGET. Interestingly (for me!), target pressures can vary for left / right tires if running on an oval, and rear / front axle to account for weight distribution, but not on a per corner basis. So that would mean setting individual cold pressures to reach P. TARGET.
Even more fascinating (again for me ), if I understand correctly, camber is to be used as well to reach P. TARGET if necessary. I guess if tires go over P. TARGET even though they were set at P. MIN (minimum cold pressure), then camber is to be used to reach hot pressure target.
I read similar recommendations on a few different sources.
Is this how the model works in Project Cars 2, with hot pressure targets mentioned on the link below?
http://forum.projectcarsgame.com/showthread.php?57541-Project-CARS-2-Tyre-Temps

Neeeext brake temps! Haha.
Hopefully you or someone from the team can clear that out. We basically want to know were peak performance is.

Ideal hot tire pressure for modern GT/LMP cars is 24-28 psi/1.6-1.9(?) bar. Brakes work best when they are 300 degrees C at the start of the braking zone. I don't know where the thread is on the PCars forums at the moment, but that should be a good start.

 

[Seb Weasel]

Ideal hot tire pressure for modern GT/LMP cars is 24-28 psi/1.6-1.9(?) bar. Brakes work best when they are 300 degrees C at the start of the braking zone. I don't know where the thread is on the PCars forums at the moment, but that should be a good start.

Thank you for your input!
However I am looking for a different information. As mentioned, Pirelli mentions a target, not a range. Real life recommendations mention various target pressures for specific uses: ovals call for different pressure left / right, weight distribution might affect front / rear. But in all cases, we are talking about a target, not a range.
I would like to know how the game works. In short, how to achieve peak tire performance? It would be much easier to follow specific instructions, such as the ones provided by tire manufacturers.

It is an important distinction because you could either consider hot tire pressure as a variable to achieve something else (mostly tire temps), or, like in real life, work on pressures with a specific goal to achieve on all 4 corners (or front/rear, left/right as mentioned above).


On a side note regarding brakes, I usually go a bit higher for steel, and quite a lot higher for carbon ceramic (LMP). When in doubt for road cars, the only way I found to determine which car was using which type of brakes: doing a "hot car" launch and looking at initial brake temps. If 550C: steel. If 650C: carbon ceramic.
Again it'd be nice to know the official peak performance temp though (in this case min/max), for all data geeks like me out there!!

 

[TexasTyme214]

So, for pressures, from what was provided above, the range overall will work anywhere, but different tracks will favor one part of the range versus another. On twisty tracks with short straights, you will lean more towards 24 psi to maximize overall grip, sacrificing for top speed. At Le Mans, Monza, Ovals, etc, 28 psi may be preferred for lower rotational resistance, giving the opposite trade-off compared to 24 psi. Most balanced tracks for me favor 26 psi, giving a balanced trade-off. In most cases, especially for endurance races, 26 psi/1.8 bar is the preferred target. This is for modern GT/LMP tires. Other tires have a much smaller range to work with. Oval cars indeed allow for much higher pressures on the loaded side, but I do not remember those target pressures.

I find that aiming for the ideal pressure in this game is more important than any other factor (camber, temperature, etc.) to reach optional tire performance. The other factors cannot be ignored, but pressure is the largest factor in my experience. In order to reach temperature targets, I find it is to just change dry tire compounds with the conditions/track rather than adjusting any suspension or alignment settings. I do not find that adjusting driving styles or alignment settings to reach ideal pressures/temperatures do not effect the tire's overall performance. All that seems to matter is getting within the temperature and pressure range.

For the brakes, it doesn't seem to be that important what the highest temperature reached in the braking zone. Your braking performance seems to be more about the temperature you initiated the braking zone with, hence the 300 C tip. That seems to work for all the racing cars in the same, regardless of brake type. It is important to make sure the brakes do not stabilize at a much higher temperature than 300 C or else you will find the tire pressures consistently increasing. This is caused by the heat from the brakes heating the air in the tires. As a test, you can do a couple hot laps. Then, slam onto the brakes to a complete stop. While the car is stationary, look at the telemetry and watch the tire pressures continue to increase.

Edit:

 

[Seb Weasel]

Thank you for taking some time to explain.
I wanted to do a bit of testing before posting again. You definitely put me on the right track with brakes. I think I was running them too hot, which meant I couldn't maintain hot target pressure. I was averaging 400C at coldest point for steel. With 300 I can now maintain 1.8 bar in most situations. Highest I've seen is 1.85 which is not too bad I think.
I agree with you, you can clearly see lap time improvements when racing at target hot pressure so I also put that at the top of the list.

Since we mentioned brakes, do you know where we can see brake wear? I saw that there was the option to repair them in the pits, but I don't see any wear indicator on the HUD.

 

[ozwheels]

To add to what @TexasTyme214 said about brakes and tire pressures. Brake ducts, pressure and balance play a big role in hot tire pressures in this game. You’ll be surprised how much you can alter your hot tire pressures with a brake balance change or duct size change. Specifically when you are at the limit of grip and have everything balanced you may be forced to use your brake ducts to set a hot pressure of 1.8/26. This is because the minimum cold pressure is really high for no reason in my opinion. Even at 18.85 psi cold you will struggle to stay at 26 psi hot on some tracks. You’ll have to open up your ducts to maintain the 26 psi. Brake Pressure affects this as well, but it’s not as sensitive.

 

[Seb Weasel]

To add to what @TexasTyme214 said about brakes and tire pressures. Brake ducts, pressure and balance play a big role in hot tire pressures in this game. You’ll be surprised how much you can alter your hot tire pressures with a brake balance change or duct size change. Specifically when you are at the limit of grip and have everything balanced you may be forced to use your brake ducts to set a hot pressure of 1.8/26. This is because the minimum cold pressure is really high for no reason in my opinion. Even at 18.85 psi cold you will struggle to stay at 26 psi hot on some tracks. You’ll have to open up your ducts to maintain the 26 psi. Brake Pressure affects this as well, but it’s not as sensitive.

Thanks for your input. Yeah I realized the impact of brake temps very recently. It makes sense I like that aspect of the game. Hot pressure target is actually what I find too low at 26, and incompatible with the model. Maybe if peak performance pressures were at 28PSI we could run hotter brakes and higher cold pressures at the same time, without having to worry about other factors. Most documentation I came across, from Michelin and Pirelli, for slicks, targets are even higher, 29 or 30. That being said minimum cold pressures are also higher, see Pirelli's example above at 21.
Just had a race with AOR in Dubai, track temp 49C, I had to run minimum pressures and compromise brake temp on rear tires with LMP2 which is nuts.

 

[ozwheels]

Thanks for your input. Yeah I realized the impact of brake temps very recently. It makes sense I like that aspect of the game. Hot pressure target is actually what I find too low at 26, and incompatible with the model. Maybe if peak performance pressures were at 28PSI we could run hotter brakes and higher cold pressures at the same time, without having to worry about other factors. Most documentation I came across, from Michelin and Pirelli, for slicks, targets are even higher, 29 or 30. That being said minimum cold pressures are also higher, see Pirelli's example above at 21.
Just had a race with AOR in Dubai, track temp 49C, I had to run minimum pressures and compromise brake temp on rear tires with LMP2 which is nuts.

I wouldn’t pay any attention to real life tire documents. SMS is the tire manufacturer here so just go with what they say.

 

[Bealdor]

Thanks for your input. Yeah I realized the impact of brake temps very recently. It makes sense I like that aspect of the game. Hot pressure target is actually what I find too low at 26, and incompatible with the model. Maybe if peak performance pressures were at 28PSI we could run hotter brakes and higher cold pressures at the same time, without having to worry about other factors. Most documentation I came across, from Michelin and Pirelli, for slicks, targets are even higher, 29 or 30. That being said minimum cold pressures are also higher, see Pirelli's example above at 21.
Just had a race with AOR in Dubai, track temp 49C, I had to run minimum pressures and compromise brake temp on rear tires with LMP2 which is nuts.

Real life teams don't care about tire manufacturer recommendations. They use the pressures that work best for them (which are much lower than what the manufacturers want them to use).
See Casey's response:

I've seen that data sheet too. They also have another one for British GT showing a hot pressure target of 2.0bar with minimum inflation of 1.4bar. All overruled by what teams/drivers tell us is actually used.

http://forum.projectcarsgame.com/sh...emps-pcars-2&p=1400431&viewfull=1#post1400431

 

[Seb Weasel]

@Bealdor good to know about real life teams, and that's a great feed thank you! Exactly the discussion I was looking for. Some of this stuff should really be in the manual so we don't have to ask around like this is some sort of dark magic! Or better yet available in game from the engineer. All we need is a few sentences for brakes, tires and maybe suspension values.
I mean yes tires are a bit voodoo but this being a game, we all know that there must be a very precise number for peak performance, maybe with different target value for cornering speed, tire wear etc completely independant from driver preference.
But I'm rambling again so thanks!!

SMS is the tire manufacturer here so just go with what they say.

That's exactly what I'm on about: SMS didn't say anything. Just "1.8 bar" somewhere on the internet... I was just giving real life examples since PC is targeting to be a simulation.
I'm sure there's still a lot of people out there running overinflated tires with ice cold brakes wondering why they are getting weird behaviour and what's up the physics model.

PS: I love the game! I want to understand it better.