I drove my 02 996 for two winter seasons here in CT with several snowy trips up to Vermont. I say drove because as of this year we have a third car so the 911 stays in the garage and I sold my Blizzaks.
Winter tires are a must. With my LM 25's the car handled ice and 4-5" just fine. Above that the clearance is an issue. Of course you must be super ginger with your right foot. In dry conditions the LM25's actually did ok for grip. Rainy conditions require caution as with most snow tires.
Don't forget, the 911 is at its roots a VW Bug. If you've ever driven one of those in the winter (I did, it was my first car as a teenager) then you know that that car ruled in winter. All the weight over the driven wheels.

Patrick

 

Winter tires and rear LSD will haul a 2WD quite far, especially a car with its engine hanging behind!!

 

Well I just picked up the C2 with the winter tires. I'll let everyone know how it is first snow since it's my daily driver. I can tell you that it seems more responsive than my summer tires in the 45' dry, but that could also be because they are skinnier in the back.

 

I driving C2 with snow tires, since okay to drive in snow. But when up hill under the snow with ice then watch out. Well doesn't matter is c2 or c4 still slip, other then that C2 with psm drive in snow is fine. The only thing I worry is the vehicle behind.
BMW can do it, We can too.

 

I am on my thrid winter with my C2 here in CT and with winter performance snow tires the car is really good. My previous car was and Audi S4. Other than clearance the car is great in the snow and a lot of fun with PSM turned off. Drove all last winter in a lot of snow storms and never got stuck.

I just drove back from NJ today in snow and rain with the summer tires and it was a bit slippery. I was driving faster than all and there were several SUV's kissing the medians. Winter tires will be on this week.

 

I have a 99', standard TC (no PSM) with fairly new all season pirelli p zero nero M+S 18" tires in the front.. and couple thousand miles with p7000 supersport all seasons in the rear. treads on both fronts and rears are still good.

you think i can drive up to vermont ski resorts this winter???

 

Don't forget the 959, oh that was a one of Porsche's highest performance all wheel drive cars.



Seriously though, the difference in performance between a C2 and a C4 is almost none. .2 seconds in 0-60 and .1 seconds in the 1/4 mile. But the C4 is better on the skidpad which may lead one to think it corners better?