New Tire Rack magalog came today and they did a test on "green" tires for the Prius. What was really surprising was across the 7 tires there was almost a 4mpg spread. I wonder how much more gap there would be if they could have done regular and performance tires too. It's probably a percentage type thing that's much less apparent when you only get 20-30mpg to start with.

I'd be much more concerned about braking performance and such, but it was interesting.

http://www.tirerack.com/tires/tests/tes ... ?ttid=121&