because somewhere you are "leaking compression" with bad piston rings, intake or exhaust valves or similar.
Oil leakage and loss of compression and power loss.
The compression ratio for NASCAR engines is limited to 12.0:1.
Most engines lose compression over time, but each cylinder should have roughly equal compression. Even if compression numbers are not equal, however, it's usually not worth the expense to fix this.
A cracked or broken piston will cause a loss of compression, as will cracked or broken rings. The failure of a head gasket will also cause a loss of compression, as will broken, cracked or badly worn valves or valve seats. A crack in the cylinder itself (either the sleeve or the engine block), or a crack in the head itself will cause a loss of compression. A problem with the plug threads or the threads in the head (for engines that have plugs) can cause loss of compression, and injectors (for engines that have them) can leak around the threads, either because the injector threads or the threads in the head have been damaged.
To increase compression. Sleeve valves take a lot of combustion chamber space.
compression ignition
Compression
The compression ratio in gasoline direct injection (GDI) engines is generally lower than in diesel engines due to differences in fuel properties and combustion processes. Diesel fuel can withstand higher compression without igniting, allowing diesel engines to use higher compression ratios for improved efficiency and power. In contrast, gasoline is more prone to knock at high compression ratios, necessitating lower ratios in GDI engines to prevent pre-ignition and ensure stability. This difference in fuel characteristics and combustion behavior fundamentally limits the compression ratios achievable in gasoline engines compared to diesel engines.
Higher octane is helpful for high compression engines. High compression causes the combustion to take place faster and can cause pinging and a loss of power. By using high octane with high compression you get the advantage of the extra efficiency of the high compression engine and the delivery of the combustion across the power stroke of the piston, with out pinging.
jet engines require air, compression, and combustion to make it work
Yes.
yes car engines are pulleys