The SHO will run on any octane according to Ford, what is everyone using so far and has anybody noticed a difference from say 89 to 92 in performance. I have noticed in my G8 GT that when I run 89 versus 87 I have better gas mileage and seems to run better. When I go with 92 there is no real difference in mpg but the performance is better. Of course I put my foot down more too!
