Car feels squirrely on winter tires?
 

Being from the Midwest snowstorms are common and not being able to drive isn't an option so a pair of Continental snow tires were picked up and installed on the stock STI rims. At higher speeds (55<) the car is harder to hold a line and has significant swaying making it hard to maintain a straight line unless under moderate acceleration. I'm curious if this is normal on this car with all winter tires?

Could be tires with soft sidewalls.

Tires with taller and more distinct tread blocks will squish more.
Sidewall strength also differs widely between makers and models.

Even my all seasons are noticeably squidgy-er than the primacys.

Yes this is absolutely the case. Soft side walls combined with soft compound is great for the snow but horrible for higher speed highway driving (especially on dry pavement). I run Blizzak WS70's on the OEM rims and it can be kind of scary at 55+ especially when it's windy. VERY hard to keep a straight line. I've contemplated changing to a "sport winter" but I really don't want to sacrifice the deeper snow traction. It does make the car feel new again though when I put my Pilot Super Sports on in the spring! lol

This is normal. My Blizzak WS80's were REALLY squirmy when new, but after a few hundred miles they have settled down to a more acceptable feel.

My Blizzaks ride great, stock size. Just slippery in the rain.

Did you say a pair? I bet you only put them on the rear right? Hmm, wonder why it's squirelly...

The literature that came with my brand new tires from tire rack say allow at least 500 miles for the mold release substance on the new tires to wear off.

I experienced similar unstable feeling on my new 245/35 - 265/35 Continental tires.

Here's a video I took which demonstrates how even the CAR thinks things are getting squirrely on soft, winter tires. That's what happens when you're driving on tires made of extra soft rubber.

[ame]http://www.youtube.com/watch?v=vOz-C33bloE[/ame]

it's normal for the most part. I haven't had problems with straight ahead so much, but slight deviations, like lane changes, and it's kind of like they put some extra slop in between the road and the steering wheel. Is the general sensation of slight push transforming mid turn into "oops, didn't ask for that much?" Or kind of how you'd expect if you were wearing cleats on concrete?

Good snow tires will almost automatically have a good deal of tread squirm, since individualized blocks are one of the things that makes them good in the snow. Mold release and dry rot wearing off will be part of it, too. For the most part, it just takes me a couple days to slow my hands down.

Squirmy at 130 km/h and above for me

I have the same continental tires as you and they feel exactly how you describe. I've had blizzards on my sti and rx8 and they were nowhere near as bad. I'll probably pay the extra 100 bucks next time...

What tires?

Blizzaks are squirrely in the rain, but not anymore than any other car on the snow. I've been very pleased with them the last two seasons.