Time trial with cold weather
06-06-2012, 01:34 PM
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Time trial with cold weather
On this saturday we have the second date of our local Porsche Cup, in a nice track 50 kms from Buenos Aires.
We do 5 laps time trials (no cones) in the full track divided per categories (mine is 964s,993s and old Boxsters)
My concern relates to the fact that weather is very cold this week (autumn/Fall here) so track may surely be slippery and also the engine, gearchange and brakes will need more time to get enough working temperature.
Any particular advice please?
We do 5 laps time trials (no cones) in the full track divided per categories (mine is 964s,993s and old Boxsters)
My concern relates to the fact that weather is very cold this week (autumn/Fall here) so track may surely be slippery and also the engine, gearchange and brakes will need more time to get enough working temperature.
Any particular advice please?
06-06-2012, 01:54 PM
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IHI KING!
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I would warm up your engine prior to driving hard. The brakes should be fine, depending on your brake pad choice. You may want to start with a higher cold pressure in the tires. I would be most worried about getting your tires to warm up and having good traction. If you have R-compound tires, they don't like the colder weather.
06-06-2012, 03:00 PM
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How cold is "very cold" Henry?
I have done autocrosses when the temperatures were in the mid to high 20's (Fahrenheit). "R" Tires at regular pressures under those conditions feel like you are driving on rocks.
Autocross on a truly cold day is quite different than track work in that the tires do not have a chance to heat all that much. Because the tire surface temperature and the track temperatures are both cold, there is very little mechanical grip.
In AX under those circumstances, I usually drop my pressures considerably. Were it to be significantly warmer (say high 50's) then I would probably just start with whatever my customary pressures are.
I suppose the trick is to do what the car tells you it needs you to do. If the tires feel like that are hard as rocks and are sliding around, I would be more inclined to drop the pressure rather than raise them. Note that this assumes you are not already significantly under inflated. You also can probably chalk the sidewalls and see where your roll over is after a few spirited laps.
Brian
I have done autocrosses when the temperatures were in the mid to high 20's (Fahrenheit). "R" Tires at regular pressures under those conditions feel like you are driving on rocks.
Autocross on a truly cold day is quite different than track work in that the tires do not have a chance to heat all that much. Because the tire surface temperature and the track temperatures are both cold, there is very little mechanical grip.
In AX under those circumstances, I usually drop my pressures considerably. Were it to be significantly warmer (say high 50's) then I would probably just start with whatever my customary pressures are.
I suppose the trick is to do what the car tells you it needs you to do. If the tires feel like that are hard as rocks and are sliding around, I would be more inclined to drop the pressure rather than raise them. Note that this assumes you are not already significantly under inflated. You also can probably chalk the sidewalls and see where your roll over is after a few spirited laps.
Brian
06-06-2012, 03:12 PM
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Thanks Brian!!
The activity we do is rather different from AX, we run in long race tracks were real race cars compete, only not at the same time
with no chicanes or cones, separated around 20 seconds from next guy, the best time for the five laps wins
I don´t know the way to translate Celcius to Farenheit but it will be be around 0° to 5° degrees Celcius
The activity we do is rather different from AX, we run in long race tracks were real race cars compete, only not at the same time
with no chicanes or cones, separated around 20 seconds from next guy, the best time for the five laps winsI don´t know the way to translate Celcius to Farenheit but it will be be around 0° to 5° degrees Celcius
06-06-2012, 04:27 PM
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That's pretty cold; 0 deg C is 32 deg F, which is freezing temperature. I would definitely not pump them up higher than your customary warm weather pressures. Take a few laps and see how it feels, and keep an eye on the roll over.
Just to give you some background on my thinking here regarding lower vs. higher pressure...
A tire is really like a spring..more pressure equates to a stiffer spring. In cold conditions when grip is minimal, you would want a softer suspension setting, rather than a stiffer one.
Best Regards,
Brian
Just to give you some background on my thinking here regarding lower vs. higher pressure...
A tire is really like a spring..more pressure equates to a stiffer spring. In cold conditions when grip is minimal, you would want a softer suspension setting, rather than a stiffer one.
Best Regards,
Brian
