I know that non-SVT contours are spec'd for 87 ocatane fuel and the SVT's are 91 Ocatane. But what about use who have 2.5 Duratec (non-SVT)I only i run the 89 (mid-grade) but was curious if its better to run higher octane since i have the duratec.What model/ocatane do you have/use? Since i have the V6 is it a wise decision to

run higher ocatane fuel?