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.
1. 1  the ratio of the cylinder volume enclosed by the piston at its outermost position to the volume enclosed by it at its innermost position. 2  the ratio of the volume enclosed by the cylinder of an internal-combustion engine at the beginning of the compression stroke to the volume enclosed at the end of it.