ENGINE UNIT DETAILS CYLINDER HEAD

  1. CONSTRUCTION

    1. The spark plug has been located in the center of the combustion chamber in order to achieve high engine's anti-knocking performance.

    2. The angle of the intake and exhaust valves is narrowed and set at 33.5° to realize a compact cylinder head.

    3. A taper squish combustion chamber is used to achieve high anti-knocking performance and intake efficiency. In addition, excellent engine performance and fuel economy have been realized.

    4. The exhaust port for each cylinder is merged inside the cylinder head sub-assembly to accelerate warm-up of the TWC, thus improving the fuel economy. In addition, at high engine speeds, with the effective cooling of the exhaust gases, the operation range for maintaining stoichiometric air-fuel mixture ratio is widened, thus reducing rich air-fuel mixtures and also improving fuel economy.

    5. By enlarging the merged port diameter of the exhaust port, exhaust gas back-pressure has been reduced, providing greater torque.

    6. The cylinder head bolt employs plastic region tightening bolts.

    7. The routing of the water jacket in the cylinder head sub-assembly is optimized to achieve high cooling performance.

      W139431C01

      *1

      Fuel Injector Assembly

      *2

      Spark Plug

      *a

      Intake Port

      *b

      Exhaust Port

      *c

      Exhaust Side

      *d

      Merged Port

      *e

      EGR Gas Passage

      *f

      Intake Side

      *g

      Taper Squish

      -

      -

    8. A dual injector system is used. By locating a fuel injector assembly at each intake port leading to the intake valves, injection is optimized for enhanced fuel combustion.

      Figure 1. Intake Port Image
      W139432C01

      *1

      Fuel Injector Assembly

      -

      -

      *a

      Intake Port

      *b

      Tumble Flow