Airplane engines in general are low compression air-cooled engines.
Cessna 150,172 ,182 Piper lances etc. all air cooled
They have to use a fuel that should not detonate, hence a lot of lead & 100 Octane, plus be able to flow @ altitude.
200 4 cly CI to 540 6 cyl CI. they all use 100 octane low leaded fuel, not a great fuel to race with, but it does have a lot more lead in it than any automotive fuel ever had.
About 10 times more lead.
They are not a high RPM engines either, 2200-2600 RPM max IIRC.
The cylinder heads are the worst design as far as getting the most power out of them, 90 degree turns, no short turn radius to speak of.
The engines that had to run 130 octane were the supercharged military & higher HP engines.
The 130 octane airplane fuel has not be available since I don't know when, probably 30 years ago minimum?
MBHD
