F1technical.net

Hi,
how does weather effect cars handling? I think that colder air gives more downforce and also more dragforce due to higher air density.Also engines gives more horsepower.So with colder weather shoul drop also lap times.Am I right?

tyre grip goes down when it is too could. you see that in winter testing. lap times can then be negatively affected. so there is an optimum for each track, tyre and car package

rob wrote:Hi,
how does weather effect cars handling? I think that colder air gives more downforce and also more dragforce due to higher air density.Also engines gives more horsepower.So with colder weather shoul drop also lap times.Am I right?

With colder weather you get:

Less mechanical grip
More aerodynamic grip
More drag
More power

It is a trade-off but generally lap times are slower than during summer months.

cooler temps dont always mean less traction if its to hot for the tire compounds then cooler weather will help traction

In Nascar, generally the hotter it is out the *slower* the lap times are.

Jersey Tom wrote:In Nascar, generally the hotter it is out the *slower* the lap times are.

same with drag racing

Thanks ,
yes if it to cold it can be problem to get tires up to operating temperature.
But if we compare for example day with 15C and with 35C it could be better one with 15C for faster laptimes.
I have read that with drop of every 4C engine power will be up to 1%, so we will get around 5% horsepower more.
With drop of temperature from 35C to 15C will be air desity higher by 0,082 kg/m3.
So let´s turn it in to some perfomance numbers.
Lets say that F1 car has at 35C 700hp so at 15C it will be around 735hp.
Lets say that F1 car has at 35C 850kg@200kph downforce so at 15C it will be around 910kg@200kph.
Lift to drag ratio will be the same because of increased drag force.
So if tires will have now problem to get to their operating temperature window at colder day the colder weather shoul be "faster".