L6 HEAD ver.RISING

HEAD Detail

• Aluminum casting material

  After analyzing the material of the normal head, we adopted AC4CH for higher strength and durability, and then applied T6 heat treatment.

  

• Port Design

  The intake and exhaust ports are fully machined using the latest 5-axis machining to create a seamless, step-free port shape and uniform volume, improving intake and exhaust efficiency.

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• Port margin

  While forming a large diameter port compared to normal, the margin thickness to the water jacket is ４mm for IN / EX to improve reliability against trouble. ※Margin thickness differs only in the following areas：Under IN spring seat / approx. 2.8mm Head bolt part / approx. 1.3mm

  

• Sand 3D printed mold

  The port core used to form the port during sand casting has been created by 3D printer to achieve a precise and consistent casting surface and high dimensional accuracy.

  

  

• Water Jacket design

  Using the latest CT scanning, we analyzed the normal head water jacket. In addition to increasing the cooling efficiency, we have suppressed the cooling imbalance that was likely to occur for each cylinder.

  

• Valve seat cut

  By adopting a coaxial sheet cutting method that cuts the inner diameter of the valve guide and the seat at the same time, it is possible to align the valve set length with high precision while greatly improving the adhesion between the valve and the seat. At the same time, it is possible to equalize the volume of the combustion chamber realization.

  

  

• Combustion chamber design

  The heart-shaped combustion chamber is designed to facilitate intake and exhaust flow, as well as rapid combustion. Since this design eliminates the need for welding and reshaping the combustion chamber, high compression can be achieved without any additional steps. This not only makes the process simpler but also eliminates the risk of welding distortion in the head.　

  

  

• Combustion chamber finishing

  The combustion chamber is formed by the latest 5-axis CNC machining, and the shape and combustion chamber volume between the cylinders are the same.

  

• Valve seat ring

  Order to compensate for the decrease in ring support rigidity caused by the expansion of the seat ring diameter, we increased the thickness from the press-fitting groove to the water jacket and reinforced it.