dvs_03gt

compression? and what you can do with it?

Quickshift_02GT

Compression

The compression stroke is the upwards movement of the piston in the cylinder with the valves closed following the intake stroke. This upwards motion compresses the fuel air mixture inside the combustion chamber raising the pressure. The difference between the initial volume of the cylinder and the final volume at the top of the compression stroke is known as the compression ratio. Typically this is approximately 9:1 in spark ignition engines and 15:1 for diesel engines. The compression ratio is particularly important in compression fired engines such as diesel engines. The fuel-air mix and compression ratio is critical to avoid pre-ignition which is the abnormal ignition of fuel in the combustion chamber before the combustion stroke. In diesel engines the fuel is injected under high pressure towards the top of the compression stroke. The distribution of fuel before combustion is also of interest because it effects the efficiency of combustion.


One of the easiest ways to define it...

MustangMafia

^^^ What he said....

VARifleman

It's the ratio of the initial volume and the fully compressed volume, not the difference. V{i}/V{f} not V{i}-V{f}. Everything else he said is good as far as I can tell.