Yes and no , I drove for decades daily going from 5200' - 9052' . It's not like I stopped and re-jetted on my way home from work everyday . The Blazer and K-20 ran just fine.
If you stay at a certain elevation , then it makes sense to re-jet , my ATV and snow blower are re-jetted to 8000'- 10,000' .
Is this like a physical modification or is it just turning a screw / adjusting
