Midland-
The differences go deeper, or further back, than just that. My friend's father lived in the
engine room of a WW2 destroyer, and explained that naval engines at that time were normally de-rated by 2/3 of their
power. That is, an
engine rated 1000hp was nominally rated at 1000hp for continuous duty at sea. And, it had to be proven and tested able to supply 3000 hp, fully three times the nominal rating, in combat conditions.
From the navy's point of view this made complete sense. The continual duty rating is what would keep the ship running indefinitely. The combat rating was called "Hell, it doesn't matter if the engine blows up in two hours, as long as it keeps us alive until this fight is over."
Sort of like the engines built for Indy cars: They develop roughly 10x more hp per cubic inch than production cars. But, they were built to endure the 500 miles at Indy, plus 200 more miles for the practice runs and a small
safety margin, and it was expected that if the engine didn't blow up after 700 miles--you had built it too damn heavy and heavy isn't fast.
Or the old A4 (aka "Stevedore") engine, a slow-turning gasoline engine that typically shipped with an air restrictor plate in the intake. Remove the plate, and you'd get 50% more
power immediately. But the Stevedore wa built to run forever, as they've made a reputation for doing, by turning at slow speeds with much less load than they can really handle.
I can't really say i disagree with Mercedes. I fully agree with a highly educated prof I had the pleasure to meet who once said "the gasoline is the cheapest part of the engine". Now, if there was only a way to run those stinky diesels on WVO and
route the
exhaust through the
galley for some decent fried chicken.<G>
These days...engine makers won't talk philosophy to end customers, like eveyrone else they are afraid they'll scare away the morons with
money, or besued by the "lesons"--those who don't have enough
money to be morons yet.