Combustion chamber for diesel engines with inclined engine valves

A diesel engine comprising:

• at least one cylinder defined in an engine block,
• a cylinder head having a bottom surface delimiting a combustion chamber associated to said cylinder,
• at least two intake valves and two exhaust valves associated to said cylinder, said at least two intake valves and two exhaust valves controlling respective intake and exhaust conduits formed in said cylinder head and ending up on said bottom surface of the cylinder head delimiting the combustion chamber,
• said intake and exhaust valves each having a respective valve axis which is inclined with respect to a cylinder axis of the at least one cylinder by an angle greater than 8°,
• said bottom surface comprising:
• a first flat surface portion orthogonal to said cylinder axis and located centrally in the cylinder,
• a second flat surface portion orthogonal to said cylinder axis and spaced from said first flat surface portion in a direction toward the cylinder,
• an imaginary circle orthogonal to and centered on said cylinder axis,
• a plurality of side surface portions, each tracing an arc of the imaginary circle, said plurality of side surface portions partially defining the perimeter of said first flat surface portion,
• a plurality of holes corresponding to said intake conduits and said exhaust conduits, said plurality of holes defining a remainder of the perimeter of said first flat surface portion, said plurality of holes intersected by the imaginary circle,
• said first flat surface portion connected to said second flat surface portion through said plurality of side surface portions, and
• said side surface portions having a rounded or an arched shape curving downwardly from said first flat surface portion to said second flat surface portion.