I've heard both sides -- that it doesn't help (and may hinder turning) in a 50-50 weighted car, and that it makes sense because traction is coming from the rear. I tend to agree with the latter. Right now I'm not particularly liking my traction with the Michelin Pilot Alpin PA2s I have on. Opinions?
I run four snow tires on our E30, and find a pair of sand bags in the trunk is helpful for additional traction, without adverse handling.
I run a similar set up in my E36, i.e. snow tires all the way around, and at least 80 pounds (four bags) of kitty litter in the trunk. It puts a nice amount of weight on the rear and when spring comes around, I just bring the stuff inside for the cat so it won't .... [pun alert] go to waste. I thought I heard some groaning.
<epic groans> lol In heavy snow, I just put the top down, and it adds a nice weight shift to the back!
Weight or no? The strictly mathematical engineering answer to this is weight will help for sure but it needs to be located about on top of the fuel tank, as that is the area closest to the triangulated axis point of the rear suspension. ( the footwell behind the front seats is about as close as you can come to safely secure weight) However, before you do that...you should have chosen the studless ice and snow tire rather than the performance winter tire for this application the traction performance on real snow and ice is just so much better.
I know I shouldn't complain too much about traction when I chose the performance winter tires to drive on dry roads.The bimmer is not the car I typically drive in snow. I just want to be a bit more secure when there is some snow I'm driving in. I bought two 70 lb. sand tubes and placed them in the front end of the trunk against the rear seats. They're just about directly over the rear axle. I'm thinking that will work out just fine.
