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SPXUMADBROYOLO
27-05-2015, 05:21
I'm having a problem trying to tune the tires of the Mercedes-Benz coupe dtm, on Watkins. And my front left is constantly on fire after a lap and no matter how high I set the pressure I can't get it to cool. Anyone got any tips? I'm using a wheel btw

Umer Ahmad
27-05-2015, 05:26
Front left will take a beating at this track. Try a harder compound.

You're scrubbing too much, slow down the entry.

Why do we have this notion that higher pressures will induce lower temps?

Pink_650S
27-05-2015, 05:31
Why do we have this notion that higher pressures will induce lower temps?


Less friction with the asphalt?

SPXUMADBROYOLO
27-05-2015, 05:35
Front left will take a beating at this track. Try a harder compound.

You're scrubbing too much, slow down the entry.

Why do we have this notion that higher pressures will induce lower temps?

I don't know why I haven't tried another compound will tomorrow. And because that's how you adjust the tires. Lower temps let it heat up and higher temps makes it take longer to heat up. Or am I wrong? Been tuning for a while and it seems to be a rule with alot of people online as well.

Lagoa
27-05-2015, 09:13
When you see a soft slick, medium slick and hard slick.. Are they saying that the difference between a soft slick and hard slick is the tire pressure?

Bealdor
27-05-2015, 09:15
When you see a soft slick, medium slick and hard slick.. Are they saying that the difference between a soft slick and hard slick is the tire pressure?

No. It's the tire compound. Soft slicks are faster but also wear out faster while hard slicks are slower but last longer.

Lagoa
27-05-2015, 09:23
No. It's the tire compound. Soft slicks are faster but also wear out faster while hard slicks are slower but last longer.

Ok thanks, but I also thought when you change the tire pressure up higher you take more time to get maximum grip but it also wears out slower.

BatteredSav
27-05-2015, 10:42
You're putting too much load on your front left. You can either soften your front suspension and/or sway bar or stiffen the rear.

Don Ente
27-05-2015, 11:56
Ok thanks, but I also thought when you change the tire pressure up higher you take more time to get maximum grip but it also wears out slower.

Take a look here: http://www.turnfast.com/tech_handling/handling_pressure

PeoplesChampion
27-05-2015, 12:09
No. It's the tire compound. Soft slicks are faster but also wear out faster while hard slicks are slower but last longer.

You are correct in theory, but I'm a stickler for accuracy. Soft slicks offer more grip, as they provide more friction, which almost always means faster lap times.. However, a softer contact patch will have more rolling resistance than a tire with a harder one. The difference is very little and only noticeably effects straight line speed. On modern race cars, the difference would be so little that the benefits of your straight line speed would be surpassed by the cars killing you in the corners.

An extreme example would be a car rolling on rubber tires vs. a car running on solid wheels. This is completely hypothetical, but if the wheel weighed the same as the tire, the wheel would have almost no loss of energy due to rolling resistance.

Again, I'm not saying you are wrong. I just wanted to explain rolling resistance in a nut shell.

Don Ente
27-05-2015, 12:12
In a nutshell: you want to set your tire pressure so that - when the tire has heated up - the inside, middle, and outside portions of the tread will all read at the same temperature. It's not always easy to accomplish...

A quick diagram from http://www.national.co.uk/information/tyre-pressure.aspx (note that, for racing tires / slicks, the Correct Inflation image will look much flatter):

http://www.national.co.uk/images/tyrepressureinflation.gif

As you can see --- if you OVER-inflate the tire, sure, it won't heat as fast, but you will get less and less traction (smaller and smaller contact patch) as the pressure increases.

- Don

z3r0cool77
27-05-2015, 15:07
You are correct in theory, but I'm a stickler for accuracy. Soft slicks offer more grip, as they provide more friction, which almost always means faster lap times.. However, a softer contact patch will have more rolling resistance than a tire with a harder one. The difference is very little and only noticeably effects straight line speed. On modern race cars, the difference would be so little that the benefits of your straight line speed would be surpassed by the cars killing you in the corners.

An extreme example would be a car rolling on rubber tires vs. a car running on solid wheels. This is completely hypothetical, but if the wheel weighed the same as the tire, the wheel would have almost no loss of energy due to rolling resistance.

Again, I'm not saying you are wrong. I just wanted to explain rolling resistance in a nut shell.

They're faster because the higher grip allows faster speed through the corners and thereby faster lap times. Do you really think he was trying to imply they are faster in a straight line? And even if you want to leave out corners a softer tire will still get off the line faster (exit corner faster) and even when running down a straight the increased friction is just as important to getting the power down so you are still faster down the straights as well. We're talking about applying force to induce acceleration with a crap ton more variables than would apply to your "rolling resistance" scenario, we're not rolling a rubber ball and a metal ball down a ramp. No one even mentioned rolling resistance and your example is fundamentally flawed in any case. Don't try so hard.


Front left will take a beating at this track. Try a harder compound.

You're scrubbing too much, slow down the entry.

Why do we have this notion that higher pressures will induce lower temps?

A tire under lower pressure will flex more and build up heat faster (think of bending a metal coat hanger back and forth and building up heat at the flex point) while a higher pressure tire will retain it's shape better and take longer to come up to temperature. Eventually both tires (excluding extreme pressure settings) should reach the same temp but a higher pressure tire will take longer to get there. Adjusting brake bias and suspension settings to move load off of the offending tires can also help to reduce their temp but you have to find the balance between handling characteristics that work for you and handling characteristics that work for the tires.

Umer Ahmad
27-05-2015, 15:17
If you over-inflate you can change the shape of the tyre patch like in the picture above. Too little tyre patch and the tyre "scrubs"/slides more which causes MORE heating.

This is a basic mathematics optimization problem. Yes, we do not have the exact equations unfortunately but definitely there is a "too low" and "too high" pressure region we should avoid.

Also we should consider the other "Tyre geometry" settings like Toe-in. Too much toe-in/out and the edge of the tyre "drags" across the track.

But I would generally be aware of 2 things:

1. Asymmetric tracks like Watkins, Road America etc. will punish the tyres Asymmetrically
2. Tyre compounds are you best defense against the problem
3. Adjust tyre pressures as a 2nd option
4. Adjust driving style accordingly to the track layout and track/ambient temperatures

z3r0cool77
27-05-2015, 15:33
In a nutshell: you want to set your tire pressure so that - when the tire has heated up - the inside, middle, and outside portions of the tread will all read at the same temperature. It's not always easy to accomplish...

A quick diagram from http://www.national.co.uk/information/tyre-pressure.aspx (note that, for racing tires / slicks, the Correct Inflation image will look much flatter):

http://www.national.co.uk/images/tyrepressureinflation.gif

As you can see --- if you OVER-inflate the tire, sure, it won't heat as fast, but you will get less and less traction (smaller and smaller contact patch) as the pressure increases.

- Don

As shown in the picture, a reduced pressure tire also reduces contact and grip, combined with increased flexing results in faster heat generation. In general though we aren't talking about the kind of extreme cases that cause that kind of deformation of the contact patch, just an increase in tire flex and movement aiding in heat generation.

Ultimately though "1. Asymmetric tracks like Watkins, Road America etc. will punish the tyres Asymmetrically" is really where the issue lies. Tire pressures can help with how fast or slow a tire heats up but they aren't going to solve a problem over the duration of a race. Your driving habits and how you attack corners will help as well but in the end it's unavoidable that certain tracks just eat certain tires.

Outlaw Peet
27-05-2015, 15:45
Oh man i read this thread... I have to study for a few days before i play Pcars. What a wonderfull sim!

Don Ente
27-05-2015, 15:49
As shown in the picture, a reduced pressure tire also reduces contact and grip, combined with increased flexing results in faster heat generation. In general though we aren't talking about the kind of extreme cases that cause that kind of deformation of the contact patch, just an increase in tire flex and movement aiding in heat generation.

Ultimately though "1. Asymmetric tracks like Watkins, Road America etc. will punish the tyres Asymmetrically" is really where the issue lies. Tire pressures can help with how fast or slow a tire heats up but they aren't going to solve a problem over the duration of a race. Your driving habits and how you attack corners will help as well but in the end it's unavoidable that certain tracks just eat certain tires.

No, in general we won't see extreme cases deforming the patch, however... the OP stated "no matter how high I set the pressure" --- so I think it was worth mentioning.

While tire pressure / heat *seems* simple, it's a pretty complex topic. Toe, camber, weight distribution, driving style, track conditions, etc, etc, etc all play a part.

And I fully agree with the Asymmetric tracks statement. At Road Atlanta, for example, (sadly, it's not in this game) one can go through left-side tires almost twice as fast as right-side tires!

- Don

Umer Ahmad
27-05-2015, 15:50
Oh man i read this thread... I have to study for a few days before i play Pcars. What a wonderfull sim!



Yeah dude. Also there is exam for all players coming in 2 weeks. Anyone does not pass 80% and we will disable their game key for 30 days. Start Studying!

Umer Ahmad
27-05-2015, 15:52
No, in general we won't see extreme cases deforming the patch, however... the OP stated "no matter how high I set the pressure" --- so I think it was worth mentioning.

While tire pressure / heat *seems* simple, it's a pretty complex topic. Toe, camber, weight distribution, driving style, track conditions, etc, etc, etc all play a part.

And I fully agree with the Asymmetric tracks statement. At Road Atlanta, for example, (sadly, it's not in this game) one can go through left-side tires almost twice as fast as right-side tires!

- Don

I've seen the Corvette team do Left-side only changes at Road America during the ALMS/Tudor races. NASCAR does it all the time. I can hardly think of any perfectly symmetrical tracks in the game. It's good though that the game lets you manage it how you will down to the individual tyre.

z3r0cool77
27-05-2015, 16:17
Good point that he did say "no matter how high I set them." I think when I read that I just assumed that he was talking about reasonable settings and not maxing out the pressure. Taking sliders all the way to the left or right is generally not a good idea, at least not if things are modeled properly (talking about you codemasters F1.)

SPXUMADBROYOLO
27-05-2015, 16:32
If you over-inflate you can change the shape of the tyre patch like in the picture above. Too little tyre patch and the tyre "scrubs"/slides more which causes MORE heating.

This is a basic mathematics optimization problem. Yes, we do not have the exact equations unfortunately but definitely there is a "too low" and "too high" pressure region we should avoid.

Also we should consider the other "Tyre geometry" settings like Toe-in. Too much toe-in/out and the edge of the tyre "drags" across the track.

But I would generally be aware of 2 things:

1. Asymmetric tracks like Watkins, Road America etc. will punish the tyres Asymmetrically
2. Tyre compounds are you best defense against the problem
3. Adjust tyre pressures as a 2nd option
4. Adjust driving style accordingly to the track layout and track/ambient temperatures

thanks for the information everyone. I changed the tire compound to the yiro race plus which I'm guessing is the harder compound tire and it helped alot. I hit a 1:38.042 In practice. And the tire never went into the red which is good. I eased up on my turning of the wheel and stopped most of the scrubbing as well. Thanks again

Yorkie065
27-05-2015, 16:32
It's a very interesting topic this one, and I was going to post a few more things basically saying that other aspects of the car setup affect tyre temps, not just the tyre pressure options but others have covered it in greater detail than I could have.

So, I have 2 fantastic videos for you guys of some V8 supercars, showing tyre flex which hopefully will give you a better visual understanding of what a tyre goes through during corners, bumps, crests and trophs. Seriously worth a watch as it's very cool to see!

First around Bathurst (A track in the game)

https://www.youtube.com/watch?v=ZGgWg9Q2TW8

The second around Hidden Valley
https://www.youtube.com/watch?v=1SFAt9cqZyU

z3r0cool77
27-05-2015, 17:19
Nice video :) Really demonstrates well what a tire goes through and forces that can contribute to temp and degregation.

Old skool hemi
27-05-2015, 17:26
I'm having a problem trying to tune the tires of the Mercedes-Benz coupe dtm, on Watkins. And my front left is constantly on fire after a lap and no matter how high I set the pressure I can't get it to cool. Anyone got any tips? I'm using a wheel btw

hi mate its a bug. There was a thread about it earlier.. my tyres are constantly red, doesnt matter what tune or or tyre temp, they flare up.... sorry cant help mate

BlueFin175
27-05-2015, 17:30
6-6.5 degrees of camber ... wow ! I'm not sure I have seen that much adjustment available in the game !! .. heh

fangiojr
27-05-2015, 17:34
I can tell you road race cars use different suspension settings and pressure settings dependent on side and corner on this track.

Watkins glen you will see a road racer stop and take only one side of new tires some times.

z3r0cool77
27-05-2015, 17:35
hi mate its a bug. There was a thread about it earlier.. my tyres are constantly red, doesnt matter what tune or or tyre temp, they flare up.... sorry cant help mate

I don't believe he's talking about any bug. A front corner tire, as explained repeatedly in this thread, will often overheat in relation to the other tires depending on the track. He even responds on page 2 saying he's managed to solve the issue by using harder compounds and adjusting his driving.

PeoplesChampion
27-05-2015, 17:35
They're faster because the higher grip allows faster speed through the corners and thereby faster lap times. Do you really think he was trying to imply they are faster in a straight line? And even if you want to leave out corners a softer tire will still get off the line faster (exit corner faster) and even when running down a straight the increased friction is just as important to getting the power down so you are still faster down the straights as well. We're talking about applying force to induce acceleration with a crap ton more variables than would apply to your "rolling resistance" scenario, we're not rolling a rubber ball and a metal ball down a ramp. No one even mentioned rolling resistance and your example is fundamentally flawed in any case. Don't try so hard

204789

PeoplesChampion
27-05-2015, 17:38
No, in general we won't see extreme cases deforming the patch, however... the OP stated "no matter how high I set the pressure" --- so I think it was worth mentioning.

While tire pressure / heat *seems* simple, it's a pretty complex topic. Toe, camber, weight distribution, driving style, track conditions, etc, etc, etc all play a part.

And I fully agree with the Asymmetric tracks statement. At Road Atlanta, for example, (sadly, it's not in this game) one can go through left-side tires almost twice as fast as right-side tires!

- Don

My home track!

PeoplesChampion
27-05-2015, 17:51
As shown in the picture, a reduced pressure tire also reduces contact and grip, combined with increased flexing results in faster heat generation. In general though we aren't talking about the kind of extreme cases that cause that kind of deformation of the contact patch, just an increase in tire flex and movement aiding in heat generation.

.

Where do you think that heat comes from? I will give you a hint: it's energy! Energy, that, if it were a solid wheel, as I mentioned earlier, would be retained more efficiently.

I really don't want to get in a debate with you. I'm just an internet idiot. Please, don't mind me.

Old skool hemi
27-05-2015, 18:02
I don't believe he's talking about any bug. A front corner tire, as explained repeatedly in this thread, will often overheat in relation to the other tires depending on the track. He even responds on page 2 saying he's managed to solve the issue by using harder compounds and adjusting his driving.

my mistake sorry.... still there is a tyre bug...

z3r0cool77
27-05-2015, 18:04
Where do you think that heat comes from? I will give you a hint: it's energy! Energy, that, if it were a solid wheel, as I mentioned earlier, would be retained more efficiently.

I really don't want to get in a debate with you. I'm just an internet idiot. Please, don't mind me.

There really isn't a debate to be had. It retains its energy because it lacks a VERY important variable in the calculation... Friction. Retaining energy doesn't make it any faster. You might as well be running train wheels on ice. Your energy isn't being converted to Velocity/speed/kinetic energy if you don't have friction with road surface. Again, your comparison is flawed because we aren't talking about a rolling ball. We're talking about objects under power being accelerated.

SPXUMADBROYOLO
27-05-2015, 18:28
There really isn't a debate to be had. It retains its energy because it lacks a VERY important variable in the calculation... Friction. Retaining energy doesn't make it any faster. You might as well be running train wheels on ice. Your energy isn't being converted to Velocity/speed/kinetic energy if you don't have friction with road surface. Again, your comparison is flawed because we aren't talking about a rolling ball. We're talking about objects under power being accelerated.

Thanks to everyone for your input. Glad to see this getting attention. It should help people having a similar problem. It seems the tire compund adjustment fixed the issue for this track and I think I will have to try it on road America As well. Also there isn't a bug with the tires btw.

Dynomight Motorsports
27-05-2015, 22:35
Ok take this with a grain of salt, but I did some testing and tuning in a GT3 Z4 at Silverstone. As you know Silverstone is pretty brutal on the LF. What I found first off was my Front's, particularly my RF was lifting off the ground in some of the corners under acceleration, just like the video. Also I realized I needed to dial back the Camber on my LF. Also I was running 1.85 bar on the LF averaging 105' while running 2.10 bar on the RF to add Heat to the tire. which get's in the 90-95 range. My second fix was to add more spring to the front to better balance the car. In real life; too Low psi and too High psi results in High Temps. In NASCAR a higher psi yields quicker increase in tire temps. Higher pressures are put in the tire for Qualifying. Lower Pressures are used for longer green flag runs as the tire builds pressure as it builds heat. If you don't believe me try adding pressure to you Clio Cup. The higher the pressure the quicker the Temperature build-up. So....if you want to lower your Peak Temps start with LESS Tire Pressure. Build heat quicker with Higher Pressure.