In compression ignition engines, detonation occurs near the beginning of combustion.

Since the fuel, in compression ignition engines, is injected at the end of compression stroke, therefore, there will be no pre-ignition.

To eliminate knock in compression ignition engines, we want to achieve auto-ignition not early and desire a long delay period.

In compression ignition engines, because of hetrogeneous mixture, the rate of pressure rise is comparatively lower.

1000 km/h

2000 km/h

2400 km/h

3000 km/h

fuel pump

injector

carburettor

none of these

increase

reduce

not effect

none of these

retarding the spark

increasing the engine speed

retarding the spark and increasing the engine speed

none of these