I don't have my own garage and am in a condo garage currently. And with no outlet close by for a trickle charger, etc., I will probably be driving a little here and there when temps are warm enough. Also, no place to put my Cup2s when I do get some MPSS eventually. Wanted to save the Cups for the track. Oh well. Winter is coming.

 

I'm not an authority nor claim anything of the sort, just a random internet bot with decent google-fu trying to help.

 

Fwiw, if there prove to be too many days that are too cold to run Cup 2s without a cracking risk or without feeling unsafe, or if it just becomes too inconvenient not to be able to drive the GT4 on those days (e.g. if the wife actually needs to use her own car HERSELF.... ), or I guess if the Cup 2 wear rate in general is unacceptably high despite my road mileage being fairly limited, then my current plan is to get the 19" O.Z. Leggera wheels shown for the GT4 on Tire Rack and put Cup 2s on those for exclusive track duty and then put MPSS on the stockers for year-round usage. I too drove my M3 on MPSS in weather as low as 32 F and never had a problem, though I wasn't hooning around or trying to set cornering speed records at that time either since I'm not an idiot. Never tried them in snow though, and I'm not sure that I'd want to. If I lived in a snow area, I'd probably instead keep the Cup 2s on the stockers for three-season usage and put all-seasons on 19s for adverse weather and seasons.

 

I've even been looking at tire warmers. I surrounded my stack of tires in blankets between the garage wall & tires. Last year I purchased a convection style heater with no fan to put by them. I think it cost me more than I realized in electricity.

 

Put a Snickers bar in a freezer and try to bend it. CRACK!

We are very familiar with the cold compound cracking issue. The prudent person puts the car on jackstands or removes the wheels (tires off the ground) and ignores it until spring. DON'T move a frozen tire - even enough to back the car out and run it in the driveway. DOT R compound tires (Cup 2, Trofeo R, Dunlop Sport Maxx Race, R888, Conti Force Contact) are most susceptible to cold cracking, but we have experienced the issue on summer tires like P-Zeros and N Spec Super Sports. You can read our storage articles here and here.

Bottom line? NO summer compound tire is safe from the possibility of cold cracking at or below freezing - especially as tires are becoming more aggressive in compound formulations. This issue is not covered by defect warranty.

 

The very slow cooldown in a garage might be fine, especially if the wheel is standing on those things that distribute the weight a bit. That's different from bumping around the new potholes.

Grip below 45 or 40 fahrenheit will also be so bad that you don't want to drive, leaving aside the cracking risk.

 

Experience of me and my friends at the Ridge in wash state during winter warrior lapping dec and Jan in 33-39 degree weather. 997.1 gt3s on MPSS.
Had a c7 corvette for 9 months but those MPSS tires are different. ; run flats and I would not trust them in below 40 degree weather.
Protect your car from folks sliding around on sub freezing temps. Drive another car. Use winter tires if those days occur regularly.

 

IN regards to the Pzero's, I stored my 991S in an unheated garage last year. February's average temperature was under 10'F. I didn't move the car until April and the tires were fine. I tracked on them in May with no problems.

 

Tirerack says for summer tires:But........MPSS's are not your regular summer tire according to Motortrend's test of the then new MPSS in 2011:
Link to full article: http://www.motortrend.com/news/testi...t-super-sport/

Due to being only 1/5th summer compound MPSS is less likely to crack at low temp, but if you drive it below 20F - good luck with 1/5th of the tire. If they freeze on a car that is sitting and then gradually warm-up they should be fine as long as the air pressure is high enough so that they are not overly flexed.

If interested in tire compound issues read on or buy Paul Haney's book, "The Racing & High Performance Tire." According to Paul:
Each tire has it's temp when it starts becoming a polymeric glass - AKA hockey pucks, skis. Depends on the tire. Some racing tires are too hard at 65F and some at 40F. Have slid around on the track on racing slicks at 45F where it took 4 or 5 laps to warm up to any level of traction.

 

Wow. What a great post! I learned a lot. Thank you!

 

Thanks. Happy to help. Started racing recently and tire know-how can be the difference between winning and losing - been studying up.

 

What about short periods of 30s? I'm in CA (Bay Area) and while it never really stays in super low temps sometimes we have a week or so of overnight temps in the low 30s and sometimes lower occasionally.

I park the car in the garage (uninsulated) I think it should be fine right?

I've never hung a thermometer in the garage.

 

If the garage is adjoined to the house I can't imagine you'd have an issue. Maybe just get a really cheap 1500 watt ceramic heater for those colder nights as cheap insurance?

 

This from Tire Rack:

Pirelli's warranty does not cover tires that develop compound cracking due to use in ambient temperatures below 45° Fahrenheit (7° Celsius), so the P Zero, like all summer tires, is not intended to be driven in near-freezing temperatures, through snow or on ice.

Full Article

 

Want to learn a little about glass transition?

Plasticizers are molecules that are added to polymers to reduce the glass transition (Tg) temp. When a polymer passes through glass transition, it is changed in a fundamental way and the physical properties are very different. The rule is that if the temp is above Tg, the polymer will be soft but below the Tg, the polymer will be hard.

The white plastic pipes that are used in home construction and sprinkler systems are made from PVC, a common polymer. Without plasticizers, the Tg is very high so that the pipes are rigid at room temp.

If you add plasticizers to PVC, you can drop the Tg to, say, -40C so that it is soft at room temp. That's a no go for a rigid pipe application but great for the soft white coating around your iPhone charge cord.

Back to tires. Rubber engineers add plasticizers to adjust a tire's Tg for the targeted use. Snow tires contain plasticizers so that the Tg is very low and they stay soft in the face of a good MN blizzard. Summer tires, conversely, use a lesser amount since optimal traction is the goal but the tradeoff is a higher Tg.

The bottom line is that you should not let your tires drop below Tg