So this weekend I changed over to snow tires. I've lived in Boston for 3 yrs going on 4 and decided it was finally time to invest on two sets of tires for winter/summer driving. I got 4 altimax artic snow tires for $100 185/65/15 on XXR busted rims ( thanks to the salt)
My all seasons are altimax RP 185/60/15's. I usually get between 400-430 miles to the tank in the summer. I pretty much get 55-67 miles to each notch on the fuel gauge.
The garage set the snow tires at 35psi. We get to our destination and we used up to notches on the gas gauge for a total of 39.5 miles! UGH horrible!
So upped the psi to 40 and we drove back home. 40.5 miles and used a bit under a notch on the gauge.
Its not very scientific measurement but all I can say that a higher psi on snow tires makes a huge difference. They also ride much better for longer trips. Keeps the tires from feeling so mushy.
Just my two cents

 

I think they did something like that on Mythbusters, and with a little increase in the PSI there are marginal gains in MPG.

 

i would be more concerned with traction and safety than saving a buck at the pump. pumping the tires up that much is going to make the springs and suspension components to do more work, leaving less psi in the tire will allow the tire itself to flex and in snow you want that. plus you want contact patch, running higher psi your gunna blow up the tire so your running mostly on the center of the tire, you want the whole tire to do work, especially in the snow. i dont think its a god idea, i usually take air out of my tires in the winter. summer i run 34 psi (in a tc) all around and in winter usually around 29-30 all around.

 

so i've been driving since my last post with 38psi cold/40 hot and they didn't and they ride fine! No issues with traction or anything. It snowed in boston (obv) and lowered the psi yesturday to 34 cold and the tires were amazing!
No spinning or sliding anywhere. My $100 investment paid off in 20inches of snow!

 

I have been using a set of Hankook Icebear W300's, during the winter season for the last couple of years (I only put about 2.5- 3.5K miles on per season). Excellent in the rain, or if/when going up to the montain to go skiing. I have psi at about 36-39 , and everything is fine.