I'm not as good with breaking out sentences in the copy and paste quote arena
No worries - I'm on old Forum user, so I know all the tricks!
I have these questions and comments
@TSiWRX
Please point me to some data that the intent for siped tires and snow use is to hang onto snow rather than bite for traction and then clear it, That's contrary to my old head's way of thinking. I might even see some smoke coming out
This was something that also defied my own understanding at the time, but it came from a genuine tire engineer, so I asked him a couple of follow-on questions (as you are doing now - but specifically, he pointed to the void-size -to- rotational speed behavior [winter sipes versus A/T and M/T tread void design, with the easy example being size], as well as the then known-to-me fact that ice at significantly below-freezing temperatures actually can approach the friction coefficient of concrete roadways), and it started to make sense.
That said, unfortunately, the only ready reference I was able to easily find is:
We're going to point out one of the most overlooked and important things to know about tires and how something so small can make a major impact, or help you avoid a major impact, tire siping.
www.trailbuiltoffroad.com
^ I say unfortunately because that resource also uses an empirical example instead of a more solidly factual one.
I'm in full detective mode, gimmie a bit, I hope to return with more. 🧐
Meanwhile....
The common understanding is that the winter sipe design flexes apart upon roadway contact in order to offer "more bite," but it is almost never explained exactly what it is that the tire is "biting into" (it's been pointed out to me that the language of the claims tend to be very carefully constructed - near universally [regardless of manufacturer], claims read/say that the sipes "dig deeper and harder
into snow and on ice" while "channeling away water and slush
from under the tire" - neither ever actually mentions the roadway surface itself). Empirically, on heavily snow, ice, or hardpack-covered roadways, we understand that the tire isn't really "biting into" and contacting the roadway surface, but rather, that there is just additional frozen precipitation that it's "walking over," as illustrated in this monster of a winter tire thread, on NASIOC -
The Winter Tire thread- all winter tire questions go here !!! - NASIOC (with the introductory post by TireRack's winter tire specialist, Luke). I honestly don't remember if we ever got into the snow-on-snow discussion, there, but it's possible.....
I ran the Artic Altimax tires on our 06 Passat 4-Motion the 1st year they came to this country. They were OK, but not nearly as good as Blizzaks. It was my first foray away from Blizzaks. However, They wore like iron! I wore them year round for the 2.5 years we had the car. Kind of reminded me of the Wranglers I had on the work trucks. The stock rubber on the Passat was absolutely useless! ...yes maybe even worse than the Falkens. I'm a equal opportunity tire basher
Yup. Me too. I have no allegiances.
The dual-layer Blizzak models suffered from what some would suggest to be excessive wear of that top, near-magical layer - it's a compromise (much like anything else
) - and has long been something that Bridgestone's competitors specifically attacked. At the North America introduction of the current generation of Michelin "Studless Ice & Snow" tires circa the 2008-9 winter season, the host featured comparable winters shaved to half-tread-depth: and this is precisely at this tread-depth where Bridgestone's proprietary compound is no longer present.
And once the dual-layer Blizzaks have worn past that ~half-way point, the magic dissipates (essentially a double-bogey of return to a more common winter compound, plus the now considerably less tread-depth) - which is why Bridgestone has tried to incorporate more full-depth features, starting with the current-generation WS90.
In terms of the General Altimax Arctics, without studs, their lack of top-tier compounding (combined with rather stagnant tread design: they are a copy of the old - but highly venerated - Gislaved Nordfrost 3) that stays pliable at ever-decreasing temps is likely what you felt as the difference between the two. Without studs, the majority of ice traction thus falls to compounding, and here, the Altimax Arctics simply could not match what Bridgestone throws at its R&D of ever-better refinements for its dual-layer Blizzak line. 💸💵💰
But as you noted the Altimax Arctics wore very well - and this is also thanks to its compounding and physical architecture: in being a studdable winter, both of those features need to take into account the need to "anchor" studs. Indeed, typically, "studdable winters" as a winter-tire sub-genre tends to wear not inconsiderably better (i.e. have longer treadlife) versus "Studless Ice & Snows. Similarly, we can also see the more robust nature of the compounding and physical architecture of studdable winters play out particularly in dry testing, where the less robust compounding of the "Studless Ice & Snow" tires often leads to not only quantifiable deficiencies in performance (i.e. longer stopping distances -
https://www.tyrereviews.com/Article/2021-Studless-and-Studded-Winter-Tyre-Test.htm this is a very recent test, but I've talked about this many times over the years:
Studded vs Studdless Winter Tires on Forester?, and
Wasting money on studded tires?), but also empirically in visible tread block damage.
I disagree about the reasoning Subaru may have used for coming up with a lesser tire. Everything is relative. Our 300S AWD had a better tire. It's RWD 300 counterpart came with a far lesser tire for snow. Our Ridgelines both came with a better tire right out the box. Not great, but much better. Subaru only makes AWD these days. They should have done better IMHO. I also think that AWD Subarus have far more 'traction' in snow country than sun country. They're big around here for 50 years now. ...again meriting a better stock tire.
It's not so much that the tire is "lesser" in every way - rather, it's just "lesser" in the manner that
we want it to be
, when there's wintry frozen precipitation on the ground.
The OE Falkens fare well in terms of both straight-line hydroplane resistance as well as in stopping distances (in the dry, which is what I can recall off the top of my head, the Ascent fares better than class average), both of which are in-part attributable to the tires. Similarly, it's not common to find complaints of cabin road/tire noise.
I've only been privy to a peek at what resources one tire-maker threw at their halo product, where that manufacturer worked so tightly hand-in-hand at homologation (forgive the outside link, but I wanted to be sure that readers of this thread are familiar with this term -
What is a homologated tire ?) that each brand not only supplied a test vehicle for that purpose, but also even together trained specialized, dedicated test-drivers in order to properly "tune" the characteristics of that tire. I don't for a minute doubt that these companies wouldn't give the same thought to tires which they are fitting to mainstream production vehicles.
Absolutely, I agree that these Falkens could do better in the slippery stuff - but I don't know what they may have to give up, in order to do so.
At the end of the day, I'm accepting of what is. I come to car forums to discuss the good, the bad, and the ugly from an unbiased position. I also come to learn and have already. I appreciate the discussion! I don't have brand bias. I've had as many as 4 stripes in the garage at once although I will say currently there only two. Subaru and lots of MOPAR HP
Same here! It's my daily fun - and where I also hope to learn something, too!
Oh, and I'm going to be really jealous if you say that you've got a Grand Cherokee Trackhawk parked beside your Subaru!