Anyone planning on trying out the Blizzak WS 70?

[TSiWRX]

A virtual tie among the WS70, Xi2, and Conti EWC for braking from 10mph, and accelerating to the 60ft mark.

 

Yep. The quantitative data breakdown shows just how closely matched these tires are.

 

Another thing I would like to see is a braking test on ice where there is a thin layer of water on top of the ice.

 

That would be interesting, indeed - but how to accomplish?

 

I guess what I'm trying to reason through is this:

 

A car's weight should "press" water out of the ice, at the temperatures seen at their ice rink test.

 

And since the design of current-generation friction/"Studless Ice & Snow" tires is to, at the "micro" level, displace that water film (created from the weight of the vehicle bearing down on the ice, at the tire contact patch), how to control for this test? in terms of water-film depth?

 

Certainly, I can see the value of such testing - meltwater on top of last night's black-ice, let's say, at the intersection to the main street from a secondary. Yep, that's actually where I want my tire to perform the most, actually!

 

And include the studded Nokian Hakka7 in the tests, as a benchmark. But pigs will fly before TR includes the Hakka7 in their testing.

 

So, on SubaruForester.org, a membership-led initiative has started the ball rolling, in terms of pressing Discount Tire Direct to also offer Nokian tires via their online/Internet venue.

 

I'd think that if DTD succeeds in bringing Nokians to the table, their competitors will follow-suit......

[outahere]

..........That would be interesting, indeed - but how to accomplish?

...............

 

Turn up the thermostat in the ice rink.

 

Mostly I am interested in how temperature affects ice traction for studded and non- studded tires.

 

In a 2002 report from the Washington DOT, it was asserted that:

 

"Studded tires produce their best traction on snow or ice near the freezing mark and lose proportionately more of their tractive ability at lower temperatures than do studless or all-season tires."

 

"The precise environmental conditions under which studded tires provide a traction benefit are relatively rare. The maximum frictional gain (in comparison to non-studded (not studless) tires) is found for new studded tires on smooth ice, where they have been shown to provide up to 100 percent gain in certain tests. However, the relative frictional gain of studded tires diminishes or becomes negative on roughened ice, as the temperature drops, as the studs wear, or if the comparison is made with studless tires."

 

"Studs are most effective on ice at or near 32 degrees F (0 degrees C) and lose their efficacy as temperatures drop and the ice becomes too hard for the studs to grip or when temperatures rise and ice melts to slush or wet pavement."

 

The above assertions are based on testing done in 1995 and earlier, by various organizations.

[TSiWRX]

^ Ah, I see where you're going with that. Very interesting, indeed.

 

Turn up the thermostat? That'll cause global warming!

[outahere]

And here is another ice/snow test of the Bridgestone WS70 vs Michelin Xi2:

http://www.tirerack.com/tires/tests/testDisplay.jsp?ttid=136

 

This test was arranged by Bridgestone to introduce the WS70, using tires with 6200 miles on them for the ice test, and 100 miles on them for the snow test. You can probably guess which tire won the comparison tests.;)

[TSiWRX]

^ Actually, someone on NASIOC pointed out that what the TireRack "preview" said seemed to be in contradiction with what their most recent round of ice-rink testing reports.

 

Yep, there's all sorts of ways to play the game.

[MikeNH]

Damn this thread makes my head hurt. It was so much easier with the Tacoma- the all terrain tires met the severe snow rating and they went along just fine. I was considering the Firestone Winterforce tires (going to be buying 225/50/17s) because they had solid ratings and were less expensive, which is important because I doubt I'd get even 2 winters out of the tire with the amount of driving I do. But these newer tires sound pretty damn impressive too.

[TSiWRX]

Damn this thread makes my head hurt. It was so much easier with the Tacoma- the all terrain tires met the severe snow rating and they went along just fine.

 

:lol:

 

I was considering the Firestone Winterforce tires (going to be buying 225/50/17s) because they had solid ratings and were less expensive, which is important because I doubt I'd get even 2 winters out of the tire with the amount of driving I do. But these newer tires sound pretty damn impressive too.

 

If you're tight on cash, the Winterforce ain't all *that* bad.

 

OK, OK, all the data says that they are, but truthfully, they'll move in snow, where all-seasons might not - and what's more, there's still more of a safety margin than without: so as long as you keep that in-mind, and drive within the limits of the tire, I truly think you'll be better with, than without.

 

And yes, tread depth does factor into things - so you truly may be better off just purchasing new, lower-cost, winter treads more frequently, instead of banking on using the same set year after year, given your mileage.

 

Hard call to make, without having tried both tactics at least once.....

[iyzmi]

^ Actually, someone on NASIOC pointed out that what the TireRack "preview" said seemed to be in contradiction with what their most recent round of ice-rink testing reports.

 

Yep, there's all sorts of ways to play the game.

Yup, that was me who noticed that. I want to buy some 205/55/16's and there is a $60 price difference for all 4 tires between the Contis and the WS70s. The only spec that I can see that is different is that the WS70 has a 1/12" deeper tread depth. Should I save my money and get the Contis or go for the WS70s for a little extra?

[TSiWRX]

^ I honestly don't know.... It's hard to say.

 

I'd say that you'll likely have a winner, either way. I know, that doesn't help, at all.

[iyzmi]

Well if they're as close as people say they are, I'll probably go for the Contis and save my money. The current $50 gift card promo on TR goes till October so I'll hold off till then in hopes of some more reviews. You guys don't think the tires will be more expensive by then do you?

[stevehecht]

I haven't checked TR lately, but I bought a set of ExtremeWinterContact from TR and they gave me a free GPS (TomTom Easy). If you need one (or another one) that's a pretty good deal, but maybe that's expired by now. I decided not to wait to see how the WS70 tested out, because full results won't be known until mid-winter. I doubt there will be an appreciable difference overall. Chances are that the WS70 will have an edge on ice and the EWC will have the slight advantage in snow and slush, but only time will tell!

[iyzmi]

205/55/16 don't qualify for the GPS because they don't cost enough.

[iyzmi]

I'm more worried about snow and slush traction than ice traction to be honest. What makes you think the EWC will outperform the WS70 in snow?

[stevehecht]

I'm more worried about snow and slush traction than ice traction to be honest. What makes you think the EWC will outperform the WS70 in snow?

 

It's really too early to say anything definitive about this, so that's why I heavily hedged my statement. Chances are really best that these two tires will be so close in performance as to be almost irrelevant. As TSi+WRX and I have recently discussed, when tire performance is this similar other factors come to the fore.

 

But to try to answer your question: The only place (AFAIK) these two tires have gone head-to-head is here: http://www.tirerack.com/tires/tests/testDisplay.jsp?ttid=135 and the tires were tested on dry roads and on ice, not in the snow or slush. The only specific finding in this test that might have some bearing on the slush question is wet braking, and here the EWC outperformed the WS70 by 2.43%, or 3.5 feet. Other relevant data might include CR giving a slight advantage to EWC over the WS60 in the overall rating (74 to 72) where snow and ice handling are weighted most heavily (although the WS60 had a better hydroplaning rating). Another piece of possibly relevant data comes from the 2009 NAF test http://translate.google.com/translate?js=y&prev=_t&hl=en&ie=UTF-8&layout=1&eotf=1&u=http%3A%2F%2Fwww.naf.no%2FForbrukertester%2FDekk%2FDekktester%2FVinterdekktest-2009%2FPiggfrie-dekk%2F&sl=auto&tl=en, where the European version of the EWC outscored the Bridgestone Nordic WN-01 on snow and slush in all categories, while the Bridgestone outscored the Conti in three out of four categories on the ice. Now the WN-01 and the WS60 both came out after the WS50 was retired within a year of each other, but I don't know how they compare in terms of performance. Of course, we also have to assume that the WS70 improves on the performance of the WS60 and the WN-01, but we don't know by how much.

 

As you can see there is a lot of inference going on here because of very inadequate data. The bottom line, as I have said, is that I really doubt that there will be very much difference between the WS70 and the EWC, although in the TR test already mentioned http://www.tirerack.com/tires/tests/testDisplay.jsp?ttid=135 the WS70 came in third in the overall testing after the EWC and the Xi-2--but, then again, there was no snow testing done! Inadequate data rules the roost here, I'm afraid.

[Zephrant]

Anyone able to buy these yet this year? My local shop says they are "on nation wide allocation", but they should get some in about 4 weeks. Tirerack.com claims to have them in stock, but a few other places are still advertising "Shipping in September". I've got a guy at Costco checking with their distribution now. They have the LM22 in stock. I want a set of 215/45R17 and will buy them now, but would prefer to get them locally so I get free lifetime balance/rotate. I have Costco on all my other cars, so that makes them a one-stop shop for me.

[Zephrant]

Costco can't order them yet. Tirerack took my order, I'll post again if they show up.

[Zephrant]

Well, I got them in the mail yesterday. They look great to me. I'll hold on to them until the weather turns more, then take them down to Costco and have them put on my stock rims.

 

I hope to by new rims/tires for summer use. My existing tires are edge worn, so I'll do an alignment after the new tires are on too.

[iyzmi]

Just got the Conti's on my WRX. I have hit a little bit of snow on them, which they do extremely well on; but I HATE driving on them on dry roads. I regret not getting performance winters because these are just awful on the road. I can't even get on the highway without squirming around under normal acceleration, they are just soo mushy. I knew winter tires were bad in the dry, but I didn't expect them to be THIS bad... I'm running them at 33psi right now, maybe I should bump up the pressure a bit?

[Mr. Sinister]

I'm running them at 33psi right now, maybe I should bump up the pressure a bit?

 

Yes. I'm currently running +4 all the way around over OEM recommendation for any tire, putting them at 37F/36R for my car. I don't think I've ever gone lower than +2. Also, remember that new tires will be extra squirmy for the first 500 miles or so before they're broken in. That may be making them worse than they would usually be.

[iyzmi]

37psi it is. I will report back if my impressions change.

[Mr. Sinister]

37psi it is. I will report back if my impressions change.

 

FYI, I've got a Spec. B so the OEM specs are 33F/32R. I believe it's different if you've got a GT. Either way, it wouldn't really hurt as long as you stay under max pressure for your tires and you maintain the correct F/R ratio.

[iyzmi]

I have a WRX with 205/55/16 tires.

[Zephrant]

I got my WS70s on the LGT a month or so ago. I've been on compact snow and ice for many days on them, and they are working great. My Wife's Forester has some 8 year old studs, and the new WS70s outperform them, even on ice.

 

My driveway has a uphill switchback that ices up. I go up it without issue, her car slips and wants to slide off down-hill.

 

Granted, the studs are old. Maybe 25% or more of the studs are missing or worn enough to not make contact. I'll be getting her a new set of WS70 tires next year I suspect.

[outahere]

I got my WS70s on the LGT a month or so ago. I've been on compact snow and ice for many days on them, and they are working great..............

 

If you're lucky, you will get freezing rain Wednesday morning.

Let us know how they do under those circumstances.

[TSiWRX]

My mother-in-law's WS70s are doing great. Fitted to her '08 Camry, she's got no problems so far.

 

I have not had extensive seat-time in it, though. From what little I've had, they seem to be less precise than my wife's Xi2s, but both fitment as well as chassis differences may be more to blame (also, I have not played with the fill-pressure on the Camry, so that's undoubtedly playing a hand at it, too).