I should have better explained my point. Their fuel efficiency is atrocious, their power output is pitiful given the size and mass, and they require leaded fuel

I should have better explained my point. Their fuel efficiency is atrocious, their power output is pitiful given the size and mass, and they require leaded fuel, as paulryanrogers mentioned. My point wasn't that they're ahead of their time. Engine technology has of course improved in the last 60 years. My point was that they've stuck around. Of course, there are examples of long-lived software, too.