Hour 66 was my High Performance check ride. In the plane world, "High Performance" means planes with more than 200 horsepower.
Car drivers might scoff at that number. Motorcycle drivers might understand. Given that the planes I fly weigh somewhere between the weight of a motorcycle and that of a car, well there you go. There's also more for a pilot to deal with in a HP plane than in a car. These planes are also air-cooled and carbureted and the pilot controls the mixture. A single flight will take one to areas of higher and lower temperature and pressure (due to altitude mostly, but distance also). Most cars don't change their situation that quickly, and modern ones have computers that deal with it even if it does happen.
So what's a HP check ride about? Managing engine temperature. Managing propeller angle and manifold pressure. This has to do with a variable pitch propeller which is much more common in HP planes than regular ones. The propeller control functions sort of like a gearing system does on a car - it manages the load on the engine during climb out and cruise.
I decided to get my HP rating so that I could take 4 people and full fuel on trips. The regular planes allowed for one or the other, but not both. Now I've got my rating and my checkout in our club's 182, so I'm good to go whenever the plane is free.