Confusion about winter testing at Circuit De Catalunya

[MrBlacky]

Hello,

I hope I'm in the right subforum.


I wonder about the results of the official qualifying at Spain.

You can view it here: http://www.motorsport-total.com/f1/erge ... 5/51.shtml
(It's a german source, but everyone should understand it)

RedBull at 1.20 and all the rest just below 1.21s or higher.

So, if you now take a look at the official winter testint at Catalunya you will see that the times were even faster - in fact of an old car like the MGP01 one.

http://www.motorsport-total.com/f1/test ... 0&zey=2010

You can say only the RedBulls have increased their speed.

So can anybody tell me why? Did they run a different layout?

Thanks in advance.

[Blackout]

Barcelona's track is allways faster in winter than in the GP... and some teams did not show their real speed for different reasons.

[scotty86]

The track would surely have been very well rubbered in with the cars doing so many laps during testing. You can see what a huge difference this makes from the young driver's test in Abu Dhabi. Also as Blackout said, some teams did not show their real speed, most likely running without any ballast and so on in an effort to gain sponsors (ie, Sauber).

[hollus]

It is the same every winter. The temperature is some 20 degrees colder in those tests than later in the race, meaning the engine has more power available and the aero works better due to the increased air density with the colder temperatures.
http://en.wikipedia.org/wiki/Density_of_air

[MrBlacky]

Ok thanks.

It is the same every winter. The temperature is some 20 degrees colder in those tests than later in the race, meaning the engine has more power available and the aero works better due to the increased air density with the colder temperatures.
http://en.wikipedia.org/wiki/Density_of_air

But that means colder track surface as well.

[hollus]

Yup, colder surface, and also more drag, but drag is not so important in Barcelona.

It also means that the tires are working at a higher differential of temperature to the environment. If a tire's optimum temp is say 110C, and the track and air temperature are 10C, the tire is working 100C above the environment temperature. In may, with a 30C environment, the same tire would only be 80C above the environment.
Question for the tire boffins:
Does that mean that the tire can take more work while operating at the ideal temperature? Would this make the cars faster? Or the temperature differential doesn't matter? Would this colder track reduce grip, or improve it (once the tires are up to temp themselves)?

[MrBlacky]

I would say the warmer the track is the more grip the track has itself, because hot rubber is like very thick glue if you know what I mean.

[lolzi]

But a too hot tyres doesn't have as much grip as a "perfect" tyre. I think, like hollus, that the temperature differential would allow the teams to "work" the tyre more.

[747heavy]

Question for the tire boffins:
Does that mean that the tire can take more work while operating at the ideal temperature? Would this make the cars faster? Or the temperature differential doesn't matter? Would this colder track reduce grip, or improve it (once the tires are up to temp themselves)?

Not a tire boffin, but I will give it a try, perhaps JT and/or Ben can come to the rescue if I say something stupid.

In a roundabout way, yes the tire could take more "work" while still not overheating.
On the other hand the tire needs more work to get up to and maintain it´s optimum working temperature.

Now it will come down to the compound of the tire.
If you have a "fixed" compound you may struggle to get up to and to maintain it at the optimum temperature, and therefore you will struggle on a "colder track".
If your compound is/was marginal for normal/hot conditions it may benefit from the colder track/air temperature by not overheating.

It´s not a clear cut better or worse situation under these conditions.
If you still can bring your tire up to/and maintain the optimum temperature, the laptimes will, most likely, be quicker on a cold day/cold track (winter testing). Mainly due to the fact that the engines will produce more power.
If you can´t get your tires up to temp, you will struggle overall and the laptimes will be slower.

If you have the free choice between different compounds, you can run a "softer" compound in cold conditions.
This is/was done in 24h races LeMans, Nürburgring etc. where you can run the softer tire during the night, because they will last and perform at their peak, while they would overheat and quickly deteriorate during the day (higher track/air temps).

Combined with the engine power advantage it is the reason, that you normally see the fastest times during the night qualifying in LeMans (if it does not rain).

If you have a "controlled tire(one construction/one compound)" (like DTM or other Touring car/GT series) you may struggle at winter tests, if it is extremely cold and you don´t have any grip, because you just can´t bring the tire up to temp.

This can lead to some "strange" set-up solutions, because you need to make your tire "work" more, to generate the heat.
These set-ups will not work (for long) if you run them during the summer in the races (when the temperatures are higher).

It´s not unheared off, that some people/teams have developed in the wrong direction during winter testing, and have later struggled with cars which "eat or destroy" their tires quickly during the races in the summer.