I have the stock Pirelli's on my car tires on my 2014 911. I was reading the post on dry rot and saw tireracks reference not to use below 45 degrees. I always thought the cutoff was 32 degrees for some reason. I have never had a car with summer tires. I was going to drive the car all winter until it got real messy (snow) this winter .I live in New Jersey and some winters are not that bad. Last year we had nice weather till January.. What are thoughts on this. I really dont drive hard at all, I flow with the traffic and would be especially careful in the cold

 

Just back off on the loud pedal, and you'll be fine at any reasonable temperature. They wouldn't be allowed to sell these tires for street use if they were really as hazardous in the cold as people say.

Below a certain point you may risk damaging the tires themselves, though. Lots of the early C7 Corvettes were apparently delivered with cracked tires for that reason. Never heard of this happening with quality brands like MPSS.

 

I disagree with Noah. You need to follow Tire Rack's advice. Summer tires have poor traction in cold temperatures. It's not just about acceleration. It's about braking too. It's also about turning and handling and emergency situations. The traction difference is significant as temperatures drop.

 

You will lose traction starting in the low 40's

Will you notice driving around at 20MPH? No

Try taking a fast corner or hitting the gas around a corner and you will quickly find out. The grip is greatly reduced in these colder temperatures. That's why they are rated a "summer" tire.

 

^^ this too. +1

 

In an pinch, you can drive at any temperature. But, for typical continued use, I'd take my summer tires off when temps remain below 50. Let's say the temp range on a given day is 30-45 degs. Your tires will grip like hockey pucks in the morning until things warm up. You can more easily deal with acceleration shortcomings than you can the loss of steering and brack control if a sudden emergency situation is dropped in your lap. It's just not worth the risk for whatever reward you think you'll get from driving summer tires in cold temps. Summer tires off around thanksgiving, and back on around St. Patrick's day in my neck of the woods.

 

While there is nothing substantively wrong with or said in the previous responses, none address the real threat. A cold wet road. Driving summer tires on a cold wet road is not for the feint of heart. For example, I was at the track last week. Overnight temps were 38-40 and the track was cold and wet with melted frost in the AM. I went around a corner at 35 mph on a yellow caution lap. For reference, this turn is normally taken by me at 65-70 mph. The rear immediately snapped and I was along for a slow ride. When I pitted, I looked at my G force history and found that I spun at .4g. On a hot day, with hot tires that turn would pull 1.25g's at 70 mph.
Personally, I don't drive on the street if temps are below 40 on a dry road. On a wet road its 50 degrees. Time to put the Sottozero's on!!!!

 

In NE Pennsylvania, with sight of New Jersey across the Delaware River, my Sottozero's went on last week.

 

I swap out when it starts getting below 40, normally around mid-November. Last AX of the season is the first week of November so I will probably swap to my winter tire set around the weekend of the 12th/13th of November.

 

This is how I was planning to use the car. Parking it about thanksgiving and start using it around St Pat.

 

That's when mine went on as well. I basically run winters from Mid Oct to Mid April (6 months), which corresponds to the time of the year here in CT where the average nighttime temp is below 45 degrees.

 

7 Celsius (45F)

 

I've never changed out summer tires in my entire life, and drive all year long. On Turbos, Carreras, Boxster S. We often have winter daytime temps in the upper 30s/ low 40s up in the mountains where I'm caning it. Around Atlanta, winter morning temps are often low-mid-thirties. Of course, this is when I'm commuting, but at interstate speeds. Been doing so on summer tires since summer tires were invented.

Now of course I'm not advising anyone else to do so, but suffice it to say that if a person takes the time to get comfortable with the effects of the different traction circle under colder conditions, it is a completely doable proposition. I wouldn't be surprised if cold weather traction from a 305/245 summer tire combo today far exceeds mid-summer traction from a HiPo tire of 20 years ago, and certainly 30 years ago. And yet people managed to stay alive back then.

Use caution, know your car, and let your conscience be your guide.

Note: if there's frozen or freezing precip on the ground, well, that's a different story of a different horse's color.

Note Squared: the acorns get mighty annoying.

 

RTFM!
If no Instruction manual call Porsche.
Do you have 'N' spec tires?
"would be especially careful in the cold"
Until someone causes you to brake severely or change lanes abruptly and then you will know the reason for the prohibition!-Richard

 

I'd rather be safe than sorry and will not drive if temps below 45 - too many idiots on the road and why tempt fate and potential tire failure when quick evasive maneuvers or quick braking is may be required. Everyone thinks they can "get away with it" until something bad happens.