hmm, maybe nobody knows, maybe you should just put some on there and see what happens.
nobody is into making their subies rugged around here. they all like to lower them and make them all "pimped out." you know, 20's and hydros and such, haha
http://www.isrperformance.com/main.html
these springs will make you ride 1.5" higher. reduced down travel could cause some control issues. axels will prolly wear out faster too.
I would prolly just get some kyb gr2's and a good set of snow tires. The gr2's made the front end of my 92 sedan ride an inch higher. I've always pondered a way to make the rear do the same, no solutions yet, maybe a spacer like the ones in that scorpion lift.