"high altitude principal use" option from factory

[Eric75]

I recently bought my 2000 Ranger XLT 4.0 and it is running fine. It was sold to the first owner by a dealer in Colorado and the original window sticker says it has the "high altitude principal use" option.

Since I will probably never drive it in Colorado, would I get some performance gains if I change it back to standard?
My guess is that it is just a different fuel map... maybe adjusted to accept a different range of input values from the sensors.

It is pretty low on my list of priorities, but I was just curious. Thought maybe it would make an interesting discussion topic.

 

[Rifleman]

Control code required on all units sold for principal use in high altitude counties, as defined in EPA regulations, and listed in the Dealer Initial Ordering Guide. High altitude performance and/or emissions control equipment provided as required to comply with EPA regulations or general product vehicle performance acceptance standards. Also available on units for sale in high altitude fringe areas. NA with 422 California Emissions.

I would say it is just a tune. A dealer could likely make the change for you. I would imagine it's to keep the engine from running too rich with the lower percentage of oxygen by volume at the higher elevation. Cost on the option is listed as being $0.

 

[snoman6115]

well i know that higher altitude runs on lower octane gas so thats all, ur truck would probably run worse with premium and much better with 89 or 87 octane. no idea wat changes in the truck itself