[Christ]

Originally Posted by shovel

i have to imagine diesels are somewhat differently affected by altitude since their compression ratio is much more critical to combustion

That's why they make chokes.

Design the engine to run efficiently at high alt, and at low alt, it'll probably blow up, so you either set it up to only use a max amount of fuel, which is pig-rich at low alt, and perfect at high alt, or you set it up with a choke, so that it runs as a smaller displacement engine (effective displacement) at low alt, and runs "normally" at high alt.