Compare performance characteristics of SI and CI engines.

Compare performance characteristics of SI and CI engines. 
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1 Answer

Answer :

Variable/Parameter
SI Engine
CI Engine
Power output per unit weight
2.7 Kg/Kw
6.5 Kg/Kw
Power output per unit displacement
30 Kw/liter
15 Kw/liter
Acceleration
Not good
Best
Reliability
Low 
High
Fuel economy
Moderate fuel economy at both full & part load. It has poor idling fuel economy 
Better fuel economy at both full & part load, idling. 
Fuel safety
More volatile so less safer Less volatile so more safer


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