Ahemi combustion chamber shape can be found on design engines.

a. both cam-in-block and overhead camshaft
b. only cam-in-block
c. neither cam-in-block nor overhead camshaft
d. only overhead camshaft

The combustion chamber heats high pressure air that is fed by the compression system into the compression system at constant pressure. A hemispherical combustion chamber is a type of combustion chamber with hemispherical design. A hemi combustion chamber shape can be found on only overhead camshaft (OHC) design engines. 

Idon't think you can change it

Answer by checking for voltage with a neon tester;