Import-Tooner wrote:The biggest question is, what elevation are you at? I'm at 5,800 feet and I run 89 in mine. I could probably get away with 87 but I figure the extra 10 cents a gallon isn't a big deal.
Elevation is the key. The higher the elevation you are the lower octane you need. The lower elevation the higher. If you're at sea level, run 91.
I know this is reaching way back, just brows'n. You are right about altitude being a factor. Low humidity lends itself to premature ignition (ping) Combustion temp is also a factor, as well as engine load. Higher combustion temp will also cause pinging and that is usually due to enging load, the more fuel you dump into your engine the higher the combustion temp. An example would be towing a heavy trailer over the Colorado rockies with outside temps at 95 - 100 degrees (I don't know if it gets that hot in the Colorado mountains but I'd immagine it could). The outside heat, low humidity and the load could all help to contribute to pinging!
Webturtle
Edit;I stand corrected on this one! Looks like the post I quoted got it right about altitude, I was all wrong! I think I was confusing the thinner air with low humidity. Anyway I hope my credability is not shot!
Modified by webturtle at 9:31 PM 2/21/2010
Modified by webturtle at 9:37 PM 2/21/2010