I know a pilot who got his 5 hour duration on a Cessna 180 back in the
1960's. He has over 150 hours enging off time flying in the Sierra
wave. One thing he found was that after a couple hours of cold
soaking the engine, it just wouldn't start. So he also had quite a
few dead-stick landings

The barograph was attached to the firewall behind the instrument panel
and provided a good indication of engine on/off.

-Tom