Harblar, did you read those four articles?
Just askin', because I went to the trouble to provide articles from four different sources, they all came to the same conclusions, and it was quite clear that their frame of reference was vehicles with modern engine and fuel management systems.
BTW, the Ford manual makes it clear that peak torque is unchanged regardless of fuel.
Ruger, have you tested 87 vs 91 for yourself? You can post all the articles you want, but they don't mean much when real world data in the Raptor from multiple end users tells you otherwise.
When my Raptor was stock I saw mpg as high as 15.5 mpg (usually around 14mpg or better) on 91. I never saw better than 11.3 mpg using 87.
My cost for 87 is $.35 per mile. My cost for 91 is $.33 per mile (and that figure includes almost 10,000 miles of driving with long tubes, cold air, a tune, and big damn heavy 36" Toyo's. My current mpg with that setup is around 11.7mpg, which is still better than I ever got with 87. If I loaded an 87 performance tune for my rig, I bet it'd fall down to less than 10mpg running 87.)
Wilson, I've only used E30 once. I was up in Britton and it was either 87/89 or e-30. I didn't have my tuner with me so e-30 was as close to 91 as I could get. It ran ok. The mileage wasn't quite as good, but I'm sure a proper tune for e-30 would help that. It did seem to have a pretty good snap to it.
