My NA F250 lacks pyro but it does ok at 8500 with a crappy Mr Gasket 30gph pump.
Here is the area I am referring to. The circled areas are where I had problems.
The highway leading NW from CO Springs to Woodland park, I was rolling coal until I saw in my mirror, so I let off a bit. Other old vehicles were overheating/breaking down on that climb, so it's nothing to sneeze at that.
No problems around Cripple Creek or Victor, aside from slightly lacking power on hills and smoke. No problems starting/restarting. I even camped up there for about 5-7 nights up around there and had no problem starting up to leave.
Then I looped south (outside of this map area) and around back northbound to St Elmo and Leadville. That's were I had problems with it not wanting to restart. After Leadville, I ended up hurrying heading north, down to ~7,000ft in Avon, CO and the problem was gone.
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