Hi, is it just my feel or is it a known fact if PS2 tires loose traction by much in lower temperatures - like when it is below 40 degrees?

Driving yesterday in my usual route I gave full throttle leaving gas station and my rear axle definitely spinned and drifted in that turn. Steering also felt, well, not right in the beginning. It sort of restored to normal in 10-14 minutes I guess when tires warmed up but I was surprised - it was n`t too cold yet and road was perfectly dry.

 

Yes, it's a known fact.

just an example from Mobil's site:
Tire Differences
A main difference among winter tires, all-season-tires and summer tires is the pliability and durability of their rubber at different temperatures. Tire engineers call it "glass transition temperature:" Get them cold enough and every tire will have the grip of a Formica kitchen counter. For a race tire, it might be 40° Fahrenheit. For a winter tire it could be 60° below zero. Summer tire tread starts becoming Formica-like somewhere just below freezing.

 

It is correct terminology - 'glass transition'. It definitely felt like riding on a plastic. Well, then it means I will finally have to put those PA2`s on instead of PS2`s. Time has come.

Still, I find it quite weird to have this transition at 40° with PS2. Yokos feel just fine until 10° or so...

 

When I had ps2's on my M3 they wouldnt grip for crap if you tried to hit it off the line. Never really pushed it to hard through the winter months unless I knew I had them up to a good temp, but right out of the garage they definitely didn't hook like in the warm.

 

PS2's and other summer tires loose there effectiveness below 7C or 45F. As we say in Canada, they are like hockey pucks after that.

 

I have the RE050A's and they were really dicey at 45 deg. I was amazed. Car basically danced between understeer and oversteer in a couple of corners. Got the 960 Pole Positions on now and they have felt totally fine down to our current 30 deg morning temps.

 

I drive my Potenza's during sub zero temps all the time and also my Michelin's on my BMW.. Your tires are proper temperature after you have been running on them for awhile. Granted, short trips on summer tires will result in less grip, but not dangerously so and once you have driven on them for some time, they'll have similar grip as they do in summer.

 

it will be 28-29 degrees now in the night, so, it is easier to put PA2 on, as I have this set anyway... PS2 may wait until next season now. Or may be I will finish this set of PA2 completely so I could discharge them and put R-comps on those 18" rims. Will see. I am just afraid it will probably take more than 1 season to finish up PA2 tires and it makes little sense to drive on em in summer months.

 

Any performance summer tire is downright dangerous below freezing.

 

Maybe if you read the marketing matierial, but not in the real world as I described above. Most people don't even know the minor temperature difference of the tires between moderate ambient temps and freezing. Both sidewall and tread temps will be well above manufacturer's minimums.

Obviously the softer the rubber the better in cold, but running summer tires all year round is not a problem in dry weather. Remember, it is the more aggressive tread pattern on all weather and winter tires that adds to the tire's temperature increase. Also running lower pressure will increase tire temperature.

 

I think porsche quotes 42 Fahrenheit ambient as the threshold (see winter brochure on canadian website). Under this temp, they figure winter tires will work better than summers on dry pavement.

The way I see it, the winter tires are cheaper, so might as well put them on sooner than later. - problem is I absolutely love my Carrera S II wheels and can't bare the though of taking them off

I'm in CT. We haven't gotten a lick of snow, but the daily highs are in the upper 40s. As soon as the highs are in the low 40s/high30s- or we get any frozen precipitation, off go the PS2s.

Good luck,
Be Safe

 

Disclaimer: I know next to nothing, but have been using PS2's in cold weather for several years!

While definitely considered "summer" tires and rated by Michelin to lose grip below a certain temperature, I have been running PS2's year round (no snow or ice) on various high-performance cars (M3's, Boxster's and Carrera's) since they were first released to the market place and have found that after about 10 miles they warm up and grip just fine even in sub 30º temps. When on back roads with no traffic I actually weave back and forth quickly a bit to warm them up faster.

Keep in mind I never push any car beyond about 7/10ths on public roads......track use is surely an entirely different situation.

Not the best choice for winter driving, but if allowed to warm up properly and not driven on ice or snow they really should be just fine based on my experience.

 

Great thread.

I have been holding off putting on the winter tires until I read this thread. My plan was to drive the 997.2 only when its dry. I didn't think about the effect of the temperature on the tires. I usually take the scenic route home which includes country winding roads. I'm convinced I need winter tires. I just ordered a set of winter rims with tires today. Thanks for the great info.

2009 Carrera S, 6 speed, SC, basalt black/black
2009 Land Cruiser

 

I think you'll find they're actually quieter and cushion the ride a bit more, which isn't a bad thing when conditions aren't ideal for spirited driving anyway...

Check for the N rating on the tire, N0, N1, N2 indicates Porsche approved.

Enjoy
DRP

 

And this is a great excuse to get a new set of rims. My wife would not go for the idea of me getting new rims with slicks but she is A-OK with me getting new rims with snow tires for safety measures . I can switch out the snow tires for slicks during track seasons.
I ordered the Michelin Alpin PA2. 18 x 8.5 and 18 x 10 anthrite color rims. I'm excited. There is something about driving on snow that brings another element in joy of driving.