ICE, ICE, ICE

[DoomsdayJesus]

Originally Posted by dsgerbc

In terms of compromises made, Performance Winter tire and good A/S tire somewhat geared toward winter would be fairly close, so it's nothing really surprising.
A/S 3 is a good tire, don't get me wrong, but if you test it against other Michelin products of the same generation, it would have less dry grip than the PSS, more dry grip than, say PA3/PA4 perf.winters and waaaaay more dry grip than Xi3. On ice it would still be somewhat behind PA3/PA4 and waaaaaay behind Xi3.
Comparing across producers and tire grades - will complicate matters. I can believe that A/S 3 would have more dry grip than OEM Michelin Primacy and some other regular 'summer touring' tires, although that would be a nice thing to test.

That's quite beside the point though, since those A/S 3 won't get you through ice safely in a BRZ/FR-S. I'm fairly certain they are *worse* than the Michelin A4 on ice (referenced on the graph above), which itself only produces .1g in ice braking and probaly even less sideways. It's not gonna be enough to make it up the slope over 5%, and you're gonna have to crawl everywhere praying your TC/VSC can keep you out of the ditch.

Oh I'm not claiming they're better than a purpose built tire designed to specifically handle ice or snow. But for a multi-purpose, they're bleeding edge awesome.

http://www.thesmokingtire.com/2013/r...l-season-tire/
http://tires.about.com/od/Tire_Revie...port-A-S-3.htm
These could possibly be manufacturer plants but I doubt it. I'm actually considering getting a set considering how much wet weather (and how little snow, usually) we get in the Northwest.

Originally Posted by SirBrass

Most decent tires have more dry grip, wet grip... everything against the stock HP Primacy blocks of hard rubber.

That's what you get with manufacturers competing for MPG numbers. Low RR crap. I plan on wearing out the ones on my outback and replacing them because doing otherwise would be a waste, but I'm going to have to find a buyer for the ones on my BRZ.

[SirBrass]

I don't have the patience to wear out my stockers. B/c they're so hard it's going to take forever to wear them out... something like 30k miles or more. No. Thank. You.

[dsgerbc]

Originally Posted by DoomsdayJesus

These could possibly be manufacturer plants but I doubt it.

Consumer Reports tested them too, and they came out on top in their category.

[Suberman]

Originally Posted by chrisl

It is, but I doubt it would come close to a true snow tire for ice/snow performance. It's stunningly good on the dry and wet though.

The A/S plus does work well in winter, at least around freezing. I expect the A/S 3 is even better. Michelin never stands still.

[Suberman]

Originally Posted by dsgerbc

You must find a test to back up your claims or STFU.

No, that's incorrect. I can say whatever I want with no support whatsoever. You on the other hand cannot.

The difference is I know what I'm talking about and you do not.

But of course, anyone can feel free to ignore my excellent advice.

[Suberman]

Originally Posted by BRZfan

FYI:
Taken from another thread. Compliments of DESLOCK. Drive Smart, Drive Safe:

"Lastly, for all you AT owners, from page 173 of the owners manual: "Use snow mode for accelerating and driving on slippery road surfaces such as snow."

,http://www.ft86club.com/forums/attac...1&d=1386759431

I use snow mode in my automatic equipped Jaguar. Works as advertised. Or you can manually start off in second gear which is primarily what snow mode does for you.

[Suberman]

Originally Posted by chrisl

I would believe that the A/S Plus or A/S 3 grip well enough on snow/ice to not die or slide off the road in most cases (as long as you drive carefully), but I very much doubt that they're anywhere close to the performance of a high performance snow tire on snow or ice (Michelin PA4s, for example).

Correct, no all season can handle winter like a true winter tire. However, the margin between the two tire types has closed a lot in the last few years.

Nokian WR is an example of an all weather tire.

[utekineir]

Originally Posted by Suberman

No, that's incorrect. I can say whatever I want with no support whatsoever. You on the other hand cannot.

The difference is I know what I'm talking about and you do not.

But of course, anyone can feel free to ignore my excellent advice.

[Porsche]

Dear @Suberman and @dsgerbc,

You, know, odd as this may sound, I have had a nagging suspicion for some time now that the two of you are actually on the same page, or very close. Your differences seem relatively minor, and you seem to agree on most points. Your dispute appears to arise more out of misunderstanding than actual major differences in beliefs.

If each of you could possibly release your grip on the other guy's throat, take a few steps back, and review, reflect, and repent … I think it possible that you could both work in concert to offer the younger and less experienced owners/drivers here some usefully constructive guidance.

Then again, I could be nuts.


But, it's Christmas and 't is the season to be jolly, you know. I've always been an optimistic realist, hoping for the best.


Can we find some common ground here and work for the benefit of those who know less than we three do?

C'mon, guys. Whadda ya say?

Perhaps one of you could start by defining the four types of tires the youngsters need to know about. One of the problems causing confusion (not for the three of us, but for the uninformed) is that posters keep referring to performance winter tires without marking a distinction between PERFORMANCE winter tires vs. DEDICATED SNOW & ICE tires. For example, the Michelin PA3 is the former, while the Michelin Xi3 is the latter. Most readers are probably unaware of the distinction and are ill-prepared to choose between the two types. This thread could serve to help those readers, yes?


Y'r H'mble S'rv'nt,


-Porsche

[Suberman]

I think you're correct. Thanks for pointing it out.

The whole point of these boards is to share information.

A bit like Wikipedia the reader has to decide what's useful or even interesting, let alone accurate.

Also, a wise man understands that he only learns something when he's proved to be wrong.

[Suberman]

As for tires needed for ice:

The only ice tire currently available to my knowledge is the Bridgestone Blizzak WS series. Nobody makes a production tire that can outperform the Blizzak WS on glare ice. Bridgestone can prove it and Tire Rack confirms it.

The Blizzak is a true studless winter tire. It more or less matches studded tires to the extent that is possible. This tire technology has been around since the 70's. Metzler of Germany invented this tire compound, now part of Pirelli, because the secret is high silica content and low carbon black Metzler could make these tires in colours other than black, so they did. The tires were black with bright blue tread. We called them Metzler blues. They stuck to ice like glue and wore out like gum erasers, which isn't far off what they were. Blizzak WS perform and wear about the same.

If ice is your major winter problem consider fitting a set if these. Bear in mind that Blizzak WS generally come in fourth position in comparison tests of studies winter tires in Europe.


Most modern tires are high silica and now vegetable oils are also used to make tread stickier at colder temperatures.

Next up is the more versatile studies rubber of which Continental Extremewinter Contact is the best at the moment. Equivalent tires from Michelin include the X Ice, Pirelli makes the Winter Carving, Nokian makes the Hakkapelitta, Yokohama makes the Observ and so on.

If you're brave and skilled at winter driving or your conditions involve mainly bare roads, especially cold and wet roads, then performance winter tires are the best choice. Continental again leads the pack at the moment with their TS 850 but Michelin has their new PA4 which is expected to surpass the TS850. Nokian makes the great WR all weather tire, Pirelli makes the versatile Sottozero which outperforms all the others on cold and bare dry pavement.

All the above have the Mountain Snowflake symbol on the sidewall. All are good down to minus 40 C and work on ice, snow, rain and bare pavement up to about 7C (42F approx). On,y the WR is safe above that temperature although I know from personal experience that Sottozeros with only 5 mm (about 4/32) of tread left work as well as Continental all seasons in summer temperatures.

Finally there are various all season alternatives if you get very mild winters. Never try to get by on all seasons if you get temperatures colder than minus 10C (about 15F). Colder than this will turn all season tires into hard and useless lumps. Of the all seasons currently available I think Michelin has slam dunked the market with the Pilot A/S 3 or Plus. But, there are no performance standards applicable to all season tires. The manufacturer decides when to put M+ S on the sidewall.

Summer tires do not work for winter whether it snows or not.

[dsgerbc]

Sigh.
1) No rubber will turn to hard lumps at regular winter temps, not street rubber has "glass transition temperature" that high. Maybe in the first few minutes of driving some tires will be a bit harder than others, so take it easy before you get to the freeway. After 5 minutes of driving tires come up to temperature way above freezing (like I said - touch the tread after driving). There is nothing wrong with driving A/S tires when it's -20C. You'll have less grip than when it's warm, and maybe a *touch* less than a dedicated performance winter tire, but nothing inadequate.

2) There is no magic bullet for miraculously getting more out of a tire in every condition. The progress of recent years only tweaks the fundamental trade offs around the edges.

And trade-offs are simple: to get more ice grip you need soft sipes in rubber blocks that will absolutely diminish dry traction

To get snow traction you need water (from snow/ice melting in the contact patch) to stick to the tire so that snow will stick to it; to get good wet traction you need to tires to shed water.

There are different tire classes that represent different points on the trade-off, and employ different compounds and tread design. Comparing across different producers is hard, so within a single producer there will be a distinct difference in tires of different class. There's usually a cost involved too, so what's below is basically true for top-of-the line tires, not necessarily true of some cost-conscious tire.

a)
Summer tires (used to be called just "tires", and now more accurately called "3-season tires") have large tread blocks to grip the road, water-shedding compound and usually somewhat deep longitudal grooves along the tire, so that water has somewhere to go. The will grip dry tarmac better that any other in temps well below freezing, they will be better in the wet than any other tire. Absolutely dreadful in the snow/ice
Think Michelin Pilot Super Sport

b) (ultra)HP A/S tires are geared to people who
(i) need a bare minimum winter traction often enough not to be willing to have 3-season tires.
(ii) confused people who think that A/S tires are better in the rain.
With that, these are almost summer-like, some winter grip. Some winter grip requires a bit more siping and a touch of water-retaining compound here in there, this necessarily reduces dry and wet grip relative to a). As a trade-off, these gain some ice/snow traction. Enough for some cars, I don't think it's adequate for BRZ/FR-S and won't help you much if you encounter snow/ice.
Think Michelin Pilot Sport A/S 3
c) Regular A/S. These have a bit more grip on ice/snow and give-up some in the dry/wet. Think Micheling MXV4.

d) European winter tires, or (very similarly) performance winter. There are regular ones, like Michelin Alpine A4, or for high-performance cars, like Pilot Alpine PA3/PA4. Both are taking some advantage of compounds designed for lower operating temperatures (which are still *very* much above freezing), so their dry/wet grip would be close to regular A/S tires, and they get a bit more ice/snow grip than good A/S. And I mean *a bit*. Say .12g vs .10g on ice. That's significant, but not dramatic increase in ice/snow grip.
I'm not convinced that Michelin A4 and PA4 are much different other than tire sizing and possibly side-wall stiffness.

e) Nordic/Scandinavian winter, aka Ice and Snow winter.

These give up even more dry grip, but gain quite a bit of ice/snow. Think .2g on ice.
Rubber is *very* soft, lots of siping. These will lose a good .1g of dry grip in the cold relative to a decent A/S tire (again, due to lots of small and flexible siping), but gain that .1g on ice. Excellent snow grip, but again (remember, these have to have water stick to the rubber), dreadful in the wet at temps rise.
Think Xi3.

I drove on Xi3s in the rain around 60F. It was quite fun for me and freaking scary for my wife. I'd guess it was about .4g at most (regular A/S tire will yield more like .7g).

The whole debate of the last page or two is relevant to the question "When to put winter tires on and when to take them off". My point (backed up by a couple of tests) is that summer/All-season tires are far superior in the wet/dry to winter rubber in temperatures above freezing and there's zero point in switching until temps during your commute dip into/out of sub-freezing range.

My personal recommendation for this car:if you have to drive it no matter what the weather is and live in a climate that has a winter season -- get I&S tires even if you live in a major metro. I think even "performance winter" tire will be inadequate to get you home safely if you encounter freezing rain/ice. I think giving up .1g of dry grip everyday (and adjusting your driving for it) is well worth the .1g you'll gain on that one icy day. It will keep you on the road and will permit you to get moving.
Winter performance might be okay for a FWD/AWD car with at least 60% of its weight over driven axles. Those are not enough to safely drive home a RWD car with only 46% of the weight over driven axle.

[Suberman]

DWS are phenomenal performers as an all season tire.

Continental was among the first tire manufacturers to build a studless winter tire in the 70's, the original "Contact", and still build great tires.

[Suberman]

Well, you have two points of view now (at least). The consensus of the two boils down to this now joint recommendation:

"My personal recommendation for this car:if you have to drive it no matter what the weather is and live in a climate that has a winter season -- get I&S tires even if you live in a major metro. I think even "performance winter" tire will be inadequate to get you home safely if you encounter freezing rain/ice. I think giving up .1g of dry grip everyday (and adjusting your driving for it) is well worth the .1g you'll gain on that one icy day. It will keep you on the road and will permit you to get moving.
Winter performance might be okay for a FWD/AWD car with at least 60% of its weight over driven axles. Those are not enough to safely drive home a RWD car with only 46% of the weight over driven axle."

I agree.

Performance winter tires are for conditions where bare roads predominate, often wet. If you get ice or very severe winter conditions then dedicated studless winter tires (I&S) are the safest tires you can drive on all winter in any conditions Mother Nature throws at you. I reserve performance winter tires for my awd car and my performance car. I am having serious second thoughts about my decision to fit them to my BRZ. The grip is just not good enough for the way the BRZ handles low grip surfaces.