î î î. block grants. categorical grant. commerce clause. cooperative federalism. devolution. elastic clause. federalism. line-item vote. mcculloch vs. maryland. necessary and proper clause. new deal. nullification. reapportionment. sovereign immunity. spending clause. supremacy clause. unfunded mandates.
The compression ratio is the ratio of the volume of the cylinder and the combustion chamber when the piston is at the bottom, and the volume of the combustion chamber when the piston is at the top. Automotive engineers can improve fuel efficiency and fuel economy by designing engines with high compression ratios.
So a high-performance engine has a higher compression ratio and requires higher-octane fuel. The advantage of a high compression ratio is that it gives your engine a higher horsepower rating for a given engine weight -- that is what makes the engine high performance..