On Tue, 19 Jan 2016, Brian Kennedy wrote:
> With my '96 F150 limited slip, a few 40 lb bags of salt in the back
> does pretty well. My thought would b to put lots of weight in the back
> and carry chains until your tires need replacing, then I'd buy snows.
> As I recall, the way snow tires work is the snow gets lodged in the
> grooves and the real traction is snow to snow.
[obligatory-resume]Since 1998, I've spent almost every winter racing
mid-engined RWD cars on frozen lakes in Michigan and Wisconsin, whenever
those lakes are hard enough -- over 300 races. I've tried or raced
against virtually every snow tire made, and built a few sets of studded
tires for racing purposes. Since I don't live in Michigan or Wisconsin,
that means I've also got tens of thousands of miles towing my trailers
and racecars out to the middle of nowhere in the dead of winter.
[/obligatory-resume]
First off, the last sentence above is not right. There can be some
grip from packed snow, but that's not how they are designed to work. Snow
tires actually work the same way as all other tires: the rubber deforms
into microscopic imperfections in the road surface ( or whatever they are
rolling on ) and that interface provides traction. The increased void
ratio of off-road tires is there to give loose material ( snow, mud, etc )
somewhere to go, so it doesn't get trapped between the rubber and the road
( and interfere with the process above ).
The best snow tires use rubber compounds that stay pliable down to
sub-zero temperatures, so they can still mate with surface imperfections.
I have some custom-made racing snows on which you can manually twist the
tread blocks at 10 below. They probably wouldn't last 200 miles on a dry
road, but that rubber is soft enough to grip imperfections in glare ice.
Ironically, they are made in North Carolina! Also, modern snow tires
have a 'traction material' molded into the rubber -- recycled industrial
diamonds are a common choice, but there are a few others. This obviously
increases bite on real ice. For this reason, the old logic about
super-narrow snows is no longer important. I have run everything from
165s to 225s on my little car, and wider is faster/better in some
conditions (not all).
Second, weight is a mixed bag. It will help sometimes, and hurt
sometimes. Many of the guys I race with are huge believers in adding
ballast. My car is always by far the smallest and lightest in my class --
to the point where some guys have run as much __ballast__ as my cars
weighs ( ~1 ton ) -- but still one of the fastest. TANSTAAFL, however,
and while you have more traction as a result, you __need__ a lot more to
go/stop/turn. Appropriate tires are a much better choice. The only time
the heaviest cars win is when we have a half-frozen, slushy mix several
inches deep. On dry snow, they have no chance. On smooth ice, they also
lose.
I am not a fan of chains, or street-legal studs. Metal doesn't work
well with pavement, and neither bite into ice well. 1mm studs in snow
are near useless. I don't think either are superior to top-notch snow
tires -- basically, Blizzaks, Nokians, and a couple others. I can
literally talk snow tires all day, and at the moment, I own at least four
sets. For all of my street cars ( which were sometimes also racecars ) I
would pick up a spare set of wheels, and mount up the best snows I could
find, and I would go anywhere in any conditions. Everytime we get a big
snow, I go out and drive around in it for hours for fun.
I am positive that if Eric picks up some quality snows for his truck,
he'll be just fine, and very happy.
I'm trying to keep this as short as possible, but if we want to talk
specific tire models, I'm game. It does make a huge difference... for
example, with Blizzak LM series and WS. The former are just barely
better than all-seasons, the latter are the ones you want from that brand.
--
David Hillman
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