85 octane is normally found in high altitude areas and will perform the same as 87 octane while at altitude. If you fuel up in some place like Denver and travel across Kansas you car will still run okay until your next fill up.
I was looking at the 2011 Ford Taurus Owner Guide and it shows that the SHO engine is designed to run on regular unleaded , 87 octane or higher but for best performance use premium unleaded , 91 octane or higher
Try using a higher octane gasoline in this ATV. Many times the pinging is due to not using a 91 or higher octane fuel. A lower fuel like 85 or 87 may not be burning off as efficiently as the 91 octane which in turn will cause the pinging.
Liberty Road - 2011 was released on: USA: 5 August 2011
Regular 87 octane
Liberty Defined was created in 2011.
The cast of The Liberty Option - 2011 includes: Fabian Calvo
Premium 91 Octane is recommended by Nissan.
89 octane is recommended
There isn't a 2011 Ford Explorer Sport Trac , there is a 2010 model
The 2011 Mitsubishi Outlander-Sport has 16 valves.
According to the 2011 Ford Taurus Owner Guide : The 3.5 liter V6 engine will run normally on ( " regular " unleaded , 87 octane , " premium " unleaded will provide improved performance ) The 3.5 liter Taurus SHO engine ( I believe that has twin turbochargers ) uses " regular " unleaded , 87 octane or higher ( 91 octane or higher recommended for best overall performance )
$3.07 Gallon at 87 Octane in USA North Carolina during Feb of 2011.