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drathuu
06-03-2018, 11:58
Our league is currently racing Real Weather season in europe. Obviously its cold Track temps of 2-8 degrees, with wet, rain , snow and occasional sunshine.
We are using the Caterham SP300 for this season.

We noted something weird going on with testing car setups and tyres. As the teams are getting further into the season, identified what appears to be a bug / exploit.

Currently on a dry very cold track, Wet weather tyres are faster than slicks. Firstly we put this down to temperatures, however the wets never get hot enough to overheat and so never fade. (They efffectively are about 1-1.5 seconds faster) and can last 45 minute races in the dry (very cold). It as if the tyres get upto temperature a lot faster, however as its so cold, never overheat. They also offer far superior grip on the cold track.

Slicks are very challenging to get up to temperature.. but can in 2-3 laps.. Whats funny is all drivers have determined that the wets feel more like driving on slicks when hot.

So we changed the temperature to 30degree track temps.. Suddenly the wets were worse.. They deteriorated rapidly and behaved as you would expect a wet tyre to behave.

In summary - Using Wets on cold dry tracks is faster than slicks.. (Which weve all come to agree isnt realistic).. Im not too familiar with the tyre model, but suspect the wets get a grip mutliplier applied - to give the grip in the wet weather over slicks, this is offset in the dry, by temperature build and decay of tyre.. (However with the really cold temperatures) the decay never occurs.. and hence the multiplier gives a grip advantage

AbeWoz
06-03-2018, 12:03
if you see footage of race teams testing in winter, they pretty much always use rain tires because the compounds are softer than 'soft' slicks, so i think its realistic that they should have more grip in the ultra cold conditions. not sure about wear rate however.

Asturbo
06-03-2018, 12:06
Not only this car:

http://forum.projectcarsgame.com/showthread.php?61540-Formula-A-Quicker-with-Wet-Tyres

Bealdor
06-03-2018, 12:23
In summary - Using Wets on cold dry tracks is faster than slicks.. (Which weve all come to agree isnt realistic)..

Why is it considered unrealistic that a tire with a softer compound, working within its temperature range is faster than one that's too hard for the conditions and therefore doesn't heat up?
I think you're overestimating the influence of contact patch size on the overall grip level.

Killg0re NL
06-03-2018, 12:29
Euhm on regular cars (IRL) they recommend to, change to/use summer tires from 10 degree's and above.

So i looks to me the beheviour is correct, that they deteriate faster with 30 degrees? And the grip is less with slicks until they are up to temperature, also seems right

Keena
06-03-2018, 14:17
OK this is about bike tyres but that's because I cant find anything serious about running wets in cold conditions. That in itself is telling for me. Interesting section on ambient temps in the following article raises the point that while the tread might heat up, the carcass doesn't, which can lead to problems. The article claims that running wets in cold conditions is a miss-conception. I'm not knowledgable enough to assert either way, but I thought the tyre wall consideration a worthy one to introduce.. F1 just tested in winter conditions (it snowed on one of the days I think), but no one ran a wet tyre to do anything other than test a wet setup. I cant find anything about any other formula running wets in place of slicks. I remain to be convinced..

https://lifeatlean.com/weather-and-tyres-getting-it-right/

drathuu
07-03-2018, 07:46
Ok so what im hearing - i can run wet tyres for a 1 hour race and lap 1-2 second quicker consistently for the whole 60 minutes than the slick version on a cold track ?
I dont know any wets that will last that long consistently in the cold that long, running consistently faster laps for longer.

What it means is all members are running wets for enduro race this weeks. Even thought its completely dry track for the full race.

I take onboard the feedback, but something isnt quite right here.
Summer tyres vs winter tyres.. vs wets.. (wets - have tread to clear water) - less rubber on road (and softer), so should grip more in water than slicks, and hold in wet conditions.. (dry cold track) - they have less rubber on road, dont need to clear water, but get warmer quicker, but also get flogged out quicker - which unfortunately they dont.

I dont feel im over stating my comment, asking people to test (And i mean long tests) 30 minutes plus at consistently quicker times.

I'd be interested in the tyre model mechanics to better understand the behaviour and how it works (wet v dry v temp etc).

Keena
07-03-2018, 08:29
Ok so what im hearing - i can run wet tyres for a 1 hour race and lap 1-2 second quicker consistently for the whole 60 minutes than the slick version on a cold track ?
I dont know any wets that will last that long consistently in the cold that long, running consistently faster laps for longer.

What it means is all members are running wets for enduro race this weeks. Even thought its completely dry track for the full race.

I take onboard the feedback, but something isnt quite right here.
Summer tyres vs winter tyres.. vs wets.. (wets - have tread to clear water) - less rubber on road (and softer), so should grip more in water than slicks, and hold in wet conditions.. (dry cold track) - they have less rubber on road, dont need to clear water, but get warmer quicker, but also get flogged out quicker - which unfortunately they dont.

I dont feel im over stating my comment, asking people to test (And i mean long tests) 30 minutes plus at consistently quicker times.

I'd be interested in the tyre model mechanics to better understand the behaviour and how it works (wet v dry v temp etc).

I concur. The argument that wets run better in cold conditions and are a viable alternative for a slick tyre (in anything other than extraordinary circumstances) is not something that I can find any evidence for. Only in motorcycle land is it talked about, and as my post above suggests, the argument there is held to be a miss-conception because of the overall performance of the tyre. If the tread heats up faster than the carcass, which a wet tyre would do as its the softness of the tread that determines the justification for using it, then the integrity of the tyre is suspect as tearing and internal chemical anomalies can occur due to the varied heating. I'm starting to lean towards treating the argument that "its faster because its cold" as the well known analogy of dressing up something smelly in smart wrapping paper and expecting the recipient to be delighted with the result. Beyond my own personal feelings, I absolutely remain open to be convinced, but that will take evidence, and I cant find it. If anyone can, I will review it objectively, but opinion or hearsay just doesn't count. Until that point, in my mind, the performance of the wet tyre in cold conditions in this game is simply a function of a game physics model that represents the real world in a theoretical way but which in this instance has not performed correctly, or at least doesn't replicate the subtleties that lead to a lack of evidence for teams often and obviously using wets in cold conditions, thereby leaving behind a plentiful supply of evidence trails for lunatics like us to find.

bazzalaar
07-03-2018, 09:43
It's perfectly normal to run wets when it's cold/damp. But that's very dependent on the car, they may have SLICK/WET options, but it's possible the real life version of the "wet tyre" isn't a wet race tyre, but more a performance road tyre, which would be perfectly capable of running for long periods without over heating. To give you an example, I raced a mazda MX5 and the series ran a control tyre, which was a road tyre for all intense purposes. We ran two sets. Set one would be fairly worn, to knock the edges off the blocks and reduce tyre movement on said blocks and they would be our DRY tyres. Set two would be pretty much a brand new tyre kept for when it was very wet. Depending on weather and amount of testing/trackdays it's possible to do a season on 2-3 sets of tyres.

Although, in the case of the Caterham SP 300, you are right. A car that size/weight/speed should not be faster on wets in the dry. Even if it was extremely cold.

Keena
07-03-2018, 10:47
Obviously. But in a formula with dedicated slick compounds and a dedicated wet, we are talking about a different situation.
Instead of thinking about who is right, I'm keen to concentrate on what is right. Otherwise we get game development by committee, and we don't want that, do we?

bazzalaar
07-03-2018, 14:35
TRUE! For that car it makes no sense. I work at a certain track that has a very similar car. (was on PC1) and there's no way you'd ever run anything than a slick in the dry, no matter what the track or ambient temperature is. In theory a wet would work very quickly and offer more initial grip than a slick in cold temps. We're talking 1-2 laps here though.

What sort of lap times are being achieved on a wet when compared to a slick?

In RL a car of that type, driving in the wet, on wets, will be around 10 seconds off a good time in the dry on slicks. So I'd expect a wet tyre in the dry to still be 2-3 seconds off ultimately.. I wouldn't expect them to be any good after maybe 30 mins of driving...