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CREVICE VOLUME IS THE VOLUME BETWEEN THE PISTON AND THE CYLINDER LINER. THE EFFECT OF THIS VOLUME IS VERY APPRECIABLE ON THE ENGINE PERFORMANCE.

ADVANTAGES OF LOW CREVICE VOLUME :-

1.  AS WE CAN SEE IF WE DECREASE THE CREVICE VOLUME THEN THERE IS A DECREASE IN THE CLEARANCE VOLUME BETWEEN THE HEAD AND PISTON. HENCE COMPRESSION PRESSURE WILL BE HIGH LEADING TO BETTER COMBUSTION AND HIGHER EFFICIENCY.
2. DECREASE IN HYDROCARBON EMISSION.

DISADVANTAGE OF LOW CREVICE VOLUME :-

1. LOW CREVICE VOLUME MEANS TOP PISTON RING IS NEAR TO THE COMBUSTION CHAMBER WHICH LEAD TO MORE THERMAL STRESS ON THE PISTON LEADING TO EARLY BREAKING OF THE PISTON.

DISADVANTAGE OF HIGH CREVICE VOLUME:-

1.  HIGH CREVICE VOLUME LEAD TO DECREASE IN EFFICIENCY OF THE ENGINE DUE TO DECREASE IN COMPRESSION PRESSURE DUE TO INCREASE IN CLEARANCE VOLUME.
2. DUE TO DECREASE IN COMPRESSION PRESSURE THE FORMATION OF UNBURNED CARBON IS MORE AND THIS GETS COLLECTED IN THE CREVICE VOLUME. NOW WHEN PISTON MOVES THEN THIS CARBON LEADS TO GLAZING. MOREOVER THIS CARBON DECREASE THE HEAT TRANSFER BETWEEN THE PISTON AND LINWER LEADING TO WEAR AND CRANK IN PISTON.