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kevin kirk
16-04-2018, 03:16
Can anyone give me some advice to prevent wet tires going cold? Lowering tire pressures doesnt seem to prevent it and also has a huge effect on handling. With in 3 or 4 laps of a wet race the tire temp is dropping well below the temp that makes the tire turn blue. Its pretty much stopping me from being able to do wet GT3 races. Also I do have the season set to summer.

ELAhrairah
16-04-2018, 09:37
I am no expert or pro but:

- Adjust camber (decrease negative camber) to make sure that the tires have a maximum surface contact with the ground so that water can be disposed as fast as possible and the tires can actually heat up.

- Increase ride height to prevent bottoming out.

- softening springs

You need to make sure that the tires stick to the asphalt, increase mechanical grip as much as possible by softening the chassis and increase aero downforce as much as you can get away with competitively (top speed) and to compensate the ride height downforce loss. (when the ride height increases, the overall downforce created by underbody and diffuser will be reduced)

You can also play with the dampers/rebound etc. but I would not mess too much with them and just start with the basics.

Anukpaquito
16-04-2018, 10:11
Perfect!!

FlakNine
16-04-2018, 10:18
I am no expert or pro but:

- Adjust camber (decrease negative camber) to make sure that the tires have a maximum surface contact with the ground so that water can be disposed as fast as possible and the tires can actually heat up.

- Increase ride height to prevent bottoming out.

- softening springs

You need to make sure that the tires stick to the asphalt, increase mechanical grip as much as possible by softening the chassis and increase aero downforce as much as you can get away with competitively (top speed) and to compensate the ride height downforce loss. (when the ride height increases, the overall downforce created by underbody and diffuser will be reduced)

You can also play with the dampers/rebound etc. but I would not mess too much with them and just start with the basics.

Thanks for this. I've never been sure how to turn turn a dry setup into a wet setup, so this is a good start. It would have been good if SMS included a wet weather setup for each vehicle, along with the Stable and Loose setups.

Lakiboom
16-04-2018, 10:32
I am no expert or pro but:

- Adjust camber (decrease negative camber) to make sure that the tires have a maximum surface contact with the ground so that water can be disposed as fast as possible and the tires can actually heat up.

- Increase ride height to prevent bottoming out.

- softening springs

You need to make sure that the tires stick to the asphalt, increase mechanical grip as much as possible by softening the chassis and increase aero downforce as much as you can get away with competitively (top speed) and to compensate the ride height downforce loss. (when the ride height increases, the overall downforce created by underbody and diffuser will be reduced)

You can also play with the dampers/rebound etc. but I would not mess too much with them and just start with the basics.

Agree, decrease negative camber could help.
Soft springs help to control car on the wet road - not so such sharp reaction. But I don't sure it will increase tires temp so much.
And ride height, why I need to increase it if I don't have bottoming out at dry conditions?

I had race yesterday GT3 at SPA. And at wet conditions my time was slower a lot. All because wet tyres went to 30-40 C temperature. And I had to be very careful at turns. I think it's better to search a professional literature or videos about this question.

ELAhrairah
16-04-2018, 10:47
Agree, decrease negative camber could help.
Soft springs help to control car on the wet road - not so such sharp reaction. But I don't sure it will increase tires temp so much.
And ride height, why I need to increase it if I don't have bottoming out at dry conditions?

I had race yesterday GT3 at SPA. And at wet conditions my time was slower a lot. All because wet tyres went to 30-40 C temperature. And I had to be very careful at turns. I think it's better to search a professional literature or videos about this question.

- ride height is very important to stop body aquaplaning and to give the chassis a bit more room to "move" . Don't set it to the max but try to see how much is enough bit by bit.

- springs and roll bars are set softer to make the chassis roll more and become less stiff which decreases the chance that tires lose contact to the ground, makes them stick and helps to get more heat into them. It also increases (mechanical) cornering grip but it makes the car a bit more unstable. So you will need to find the perfect compromise, a pro would say the sweet spot, between mechanical and aero grip.

Atak Kat
16-04-2018, 11:34
- ride height is very important to stop body aquaplaning and to give the chassis a bit more room to "move" . Don't set it to the max but try to see how much is enough bit by bit.

I have to admit, I never even thought about that.... now I need to do more tests/races in the rain to try this out. I had pretty much given up on rain races.... but I'm hoping this is the reason I was getting such terrible aquaplaning even at really low speeds...

Lakiboom
16-04-2018, 11:38
Yep. But the main question was: "Can anyone give me some advice to prevent wet tires going cold?" After a few laps tires temperature goes very low, much less grip and you can't stop it with any car setup.

ELAhrairah
16-04-2018, 12:18
Yep. But the main question was: "Can anyone give me some advice to prevent wet tires going cold?" After a few laps tires temperature goes very low, much less grip and you can't stop it with any car setup.

Do what I advised and STEP ON IT. Drive fast. If you are too carefull you are slow and slow speed will never get your tires up to temp.
If AI is too fast, lower it. If online is too difficult practise alone.

Edit: also do not expect (110C+) warm weather tire temps on a cold day and during rain. Maybe when the circuit dry up but if it keeps raining forget it.

Keena
16-04-2018, 12:21
Yep. But the main question was: "Can anyone give me some advice to prevent wet tires going cold?" After a few laps tires temperature goes very low, much less grip and you can't stop it with any car setup.

Try increasing toe angle to increase scrubbing. Increase pressures can decrease rolling resistance, close brake ducts more for greater heat dissipation through the tyre, drive it like you stole it. Thats all Ive got.

Zaskarspants
16-04-2018, 12:38
This is about formula one tyres.

"A dry-weather racing tyre in Formula One generally operates at an optimal temperature of around 100 C. In contrast, intermediate spec tyres are operate at between 40C to 100C, depending on the wetness of the track, while full wets approximate 30C to 50C. "

https://www.f1technical.net/articles/1

Perhaps no need to worry about getting wets really hot if this is the same for all types of wet tyre.

ELAhrairah
16-04-2018, 13:00
okay so I did a test, and these are the results:

Car: formula Renault 3.5
Track: Watkins Glen
Weather: Wet, heavy rain
Date: summer
Time: day

Setup car:

Low spring, F&R
Low anti roll, F&R
Low tire pressure, F&R
high decreased negative camber, F&R
High Aero, 16:20
Medium ride height, rear a bit higher
Geared LSD On, 1:2, 1:3

Started with cold tires @t 25C.
After 2 laps pushing:

Tire temps: Hottest tire is around 100C when I push hard, around 80C when I drive normal pace

Nothing wrong with the tire model in the wet (maybe it even gets a little bit too hot for wet conditions, I am not an expert?). I consider this a good WET setup model to start from and to fine tune, changes can be made depending on your vehicle, your speed and the circuit.

Edit: ps. Do not accelerate on wet curbs

kevin kirk
16-04-2018, 15:06
thanks guys for the help, i will try these comments later tonight.

Mahjik
16-04-2018, 15:18
Car: formula Renault 3.5


I don't want to discount your testing, as it's great information. ;) However, the OP was using the GT3 cars and the F3.5 doesn't share the same tire. I'm interested to see what GT3 testing brings. I've done dry -> wet races with GT3 cars but maybe my race duration wasn't long enough to run into issues. It's always possible that SMS needs to tweak the cold sensitivity of the GT3 tires.

ELAhrairah
16-04-2018, 15:26
I don't want to discount your testing, as it's great information. ;) However, the OP was using the GT3 cars and the F3.5 doesn't share the same tire. I'm interested to see what GT3 testing brings. I've done dry -> wet races with GT3 cars but maybe my race duration wasn't long enough to run into issues. It's always possible that SMS needs to tweak the cold sensitivity of the GT3 tires.

IRL the basics are all the same. Having said that, I will try with a gt3 car too.

edit: tried it with the gt3 r8 and heating up the tires worked as expected. Basically I used the same parameters as my previous post. The only difference is that I also closed the brake ducts a bit more, without compromising brakedisc heat levels of course. Started with 25C tires and in the 4th lap after pushing, but not too hard, I had around 70C. If I take more time I am sure that I can get the tires up to 85C. Which is in the rain a decent operating level.

I think in the end there are a couple of factors that are very important to follow, in order to increase tire temps in rain: decrease tire pressure, decrease negative camber, drive as aggressive as possible, make sure you scrub that rubber ;), and increase the mechanical grip to push those tires on the ground. The circuit is also very important. A circuit with long straights like Spa or Le Sarthe will be very difficult to keep tire temps high, as you need to push them to keep the heat in and pushing is done in corners.

This is my opinion, it's not the holy truth. Some Japanese guy somewhere always has a better method.

hkraft300
16-04-2018, 16:33
Let the wet tires go cold. They’re made for cold wet conditions.
What you don’t want is cold and under-inflated. So adjust your setup tire pressure accordingly.
Maybe you’ll be over-inflated at the beginning of the wet tire stint, which will cool and drop in pressure.

ELAhrairah
16-04-2018, 16:39
Let the wet tires go cold. They’re made for cold wet conditions.
What you don’t want is cold and under-inflated. So adjust your setup tire pressure accordingly.
Maybe you’ll be over-inflated at the beginning of the wet tire stint, which will cool and drop in pressure.



ok so you are saying colder wet tires, that are not under inflated, provide higher grip than warm under inflated hotter wet tires?

Keena
16-04-2018, 17:37
It all depends what the designed temperature range is for the wet tyre. Until we know that its just a guessing game. Grip can be measure for differing setups/pressures etc by simply viewing the G-meter in the HUD in a sustained max grip turn. (Barcelona?) Tyres which are correctly pressured or slightly over-pressured will encounter less rolling resistance from water on the track (IMHO over-emphasised in this game), and as we all know aqua-planning speed is a function of the square root of the tyre pressure (so higher pressure = higher aquaplaning speed). In addition, under-inflated tyres will have more lateral movement of the sidewall.
I offer the following as an aid to our mutual understanding of the parameters modelled in game.
http://forum.projectcarsgame.com/showthread.php?57769-Holy-s-THE-DEMO-IS-AMAZING!!!&p=1434455&highlight=tyre+physics#post1434455

Mahjik
16-04-2018, 17:50
I think the other piece to understand is what changes you can make during race time for changing conditions. i.e. alignment changes (and others) are not going to be available mid-race.

This is what the real teams have to deal with.. Do they set the car up for rain expecting rain to happen at some point (which will make them slower in the dry), or go with a dry setup and hope the rain isn't a lot or that long in the race? Decisions, decisions... ;)

hkraft300
17-04-2018, 02:12
ok so you are saying colder wet tires, that are not under inflated, provide higher grip than warm under inflated hotter wet tires?

No I'm saying cold correctly inflated tires provide higher grip than cold incorrectly inflated tires :)

kevin kirk
17-04-2018, 04:05
so i tried the suggestions every one suggested although when trying them i didnt really know how far i can go in the changes. Most adjustments i made just seem to make the car handle to wierd to be used. The tires fall so far below were they need to be nothing seems to be able to add that much heat to it to make it up. Someone mentioned just use them cold but its so little grip i cant manage to race with it. Mostly its the tracks that have long straight and few turns like Monza or lemans were they have to much time to be able to turn cold on the straights.

Keena
17-04-2018, 06:59
so i tried the suggestions every one suggested although when trying them i didnt really know how far i can go in the changes. Most adjustments i made just seem to make the car handle to wierd to be used. The tires fall so far below were they need to be nothing seems to be able to add that much heat to it to make it up. Someone mentioned just use them cold but its so little grip i cant manage to race with it. Mostly its the tracks that have long straight and few turns like Monza or lemans were they have to much time to be able to turn cold on the straights.

Hmm, I'll have a look and see if there's anything that springs to mind.
What circuit, date, weather condition, car, etc etc- anything I can set up to replicate the conditions that are giving you an issue. IF for nothing else than to get an additional data source..

ramm21
17-04-2018, 18:18
I have an LMP2 rain race tonight @Fuji. I worked on the setup the last few days, and these are my observations-

1. Even with track temps around 60F, I have trouble keeping the front left from OVERHEATING. After a few laps, that tyre heats up a little over 220F by the last corner, but they drop to 190-200 by the end of the front straight.

2. I start with tyres at lowest pressures possible, they raise up to the 25-26 psi range after a few laps. Brake ducts at 20 front and back...

3. I put the camber as low as possible front and back, -1 and -1.5 were the values for Ligier Judd. Also softened ARBs and DF almost at max. However, even with the flattest contact patch and soft chassis/suspension settings, my tyres inside layer heats up way more than the middle or outside, especially the fronts. It almost seems like the temp spread doesnt change no matter what camber I run. Anyone else experiencing this?

Keena
17-04-2018, 19:01
I have an LMP2 rain race tonight @Fuji. I worked on the setup the last few days, and these are my observations-

1. Even with track temps around 60F, I have trouble keeping the front left from OVERHEATING. After a few laps, that tyre heats up a little over 220F by the last corner, but they drop to 190-200 by the end of the front straight.

2. I start with tyres at lowest pressures possible, they raise up to the 25-26 psi range after a few laps. Brake ducts at 20 front and back...

3. I put the camber as low as possible front and back, -1 and -1.5 were the values for Ligier Judd. Also softened ARBs and DF almost at max. However, even with the flattest contact patch and soft chassis/suspension settings, my tyres inside layer heats up way more than the middle or outside, especially the fronts. It almost seems like the temp spread doesnt change no matter what camber I run. Anyone else experiencing this?
https://www.tirebuyer.com/education/tire-pressure-and-performance

kevin kirk
18-04-2018, 04:33
Hmm, I'll have a look and see if there's anything that springs to mind.
What circuit, date, weather condition, car, etc etc- anything I can set up to replicate the conditions that are giving you an issue. IF for nothing else than to get an additional data source..

my last race was monza one hour 30 minute race,accelerated tire wear, summer time,x2 time change starting at 7 in the evening. GT3 cars within 6 laps they are stone cold. mostly default settup.

Keena
18-04-2018, 07:31
my last race was monza one hour 30 minute race,accelerated tire wear, summer time,x2 time change starting at 7 in the evening. GT3 cars within 6 laps they are stone cold. mostly default settup.

Ill have a go. It might not be till Saturday as Im in work until then and away from my pc.

hkraft300
18-04-2018, 08:28
I have an LMP2 rain race tonight @Fuji. I worked on the setup the last few days, and these are my observations-

1. Even with track temps around 60F, I have trouble keeping the front left from OVERHEATING. After a few laps, that tyre heats up a little over 220F by the last corner, but they drop to 190-200 by the end of the front straight.

2. I start with tyres at lowest pressures possible, they raise up to the 25-26 psi range after a few laps. Brake ducts at 20 front and back...

3. I put the camber as low as possible front and back, -1 and -1.5 were the values for Ligier Judd. Also softened ARBs and DF almost at max. However, even with the flattest contact patch and soft chassis/suspension settings, my tyres inside layer heats up way more than the middle or outside, especially the fronts. It almost seems like the temp spread doesnt change no matter what camber I run. Anyone else experiencing this?

It's possible.
At a track like monza, you're not cornering a lot. It has long straights, so any camber (don't forget camber increasing as the car drops from downforce) will have the car running on its inside edge therefore hotter.
When you're on the brakes, the nose dips, camber increases, inside edge takes the load.
Down the long straight at Fuji with max camber, car drops from downforce, camber increases, inside edge takes the load.

You might want to try open the brake ducts a touch and stiffen the swaybars. Maybe your car is leaning too much? If your roll stiffness is too soft, even on left turns the inside edge of the left tire is on the ground from the car rolling.

ELAhrairah
18-04-2018, 18:10
Anyone experience with toe-in settings for long straights, to keep the tires scrubbing so that they lose heat a lower rate?

kevin kirk
19-04-2018, 03:52
Anyone experience with toe-in settings for long straights, to keep the tires scrubbing so that they lose heat a lower rate?

I tried a couple of clicks either way but it effect the handling to much to be used

kevin kirk
19-04-2018, 03:53
I should also mention im using controller

ELAhrairah
20-04-2018, 17:30
I should also mention im using controller

Are you kidding me son? Get the hell a wheel with proper ffb asap to enjoy the fullest of this game!

Cholton82
21-04-2018, 19:18
I had a race in the WSCC in the Audi R8 GT3 at Daytona today , It's a night race and the track and air temps are cold .
My race was going well holding P3 and being within 0.6 of a second lap after lap of p2 , then the rain came down .
I pitted for wets from a preset strategy , think my pressures were around 23psi and it was like driving on glass , no grip whatsoever and I soon tumbled down the order , couldn't turn in and couldn't get any power down almost like I was back on slicks however I saw them fit wets . I was using the default loose setup as this was quick for me in practice and qually and I didn't know it was going to rain in the race , but is the loose setup really that bad in the wet at those really low temperatures as it seems ok with higher track temps in the wet .