Octane lower at higher elevations

Skipg wrote:
I've noticed at higher elevations the octane levels are lower than what I am used to.I always use regular 87 octane at higher elevations my choice here is 86 or 88 octane. What should I use. I have a 2006 Ford V10. Thanks
Skip G

Skip, I live in Washington State, when I would ride my Harley Davidson to Sturgis, South Dakota for bike week. I noticed the octane would lower when I was headed East on I-90 after leaving Idaho! I had friends who I rode with that would adjust there ignition module (under there seat) to deal with the lack of octane! Very interesting question!