Abstract: A pair of main molds forming an outer peripheral face of a piston and a pair of side cores forming the pair of cutout recess parts of the piston are prepared, the main mold and the side core are set so as to form a cavity corresponding to the piston, the cavity is charged with molten metal, and when the side core is moved downward and in a direction away from the central axis of the piston so as to carry out mold release from the cutout recess part after the piston within the cavity has solidified, the side core is tilted in a direction in which an upper end thereof approaches the central axis of the piston. Thus, it is possible to release a core smoothly from a cutout recess part without it biting into an inside face of the cutout recess part.

Abstract: A pair of main molds forming an outer peripheral face of a piston and a pair of side cores forming the pair of cutout recess parts of the piston are prepared, the main mold and the side core are set so as to form a cavity corresponding to the piston, the cavity is charged with molten metal, and when the side core is moved downward and in a direction away from the central axis of the piston so as to carry out mold release from the cutout recess part after the piston within the cavity has solidified, the side core is tilted in a direction in which an upper end thereof approaches the central axis of the piston. Thus, it is possible to release a core smoothly from a cutout recess part without it biting into an inside face of the cutout recess part.

Abstract: An engine control system for an automotive vehicle for controlling slippage through fuel-cut and ignition retardation makes a correction in which an engine output control parameter is changed smaller every time a low slippage continuing time reaches each of predetermined threshold times so as to increase engine output, thereby improving acceleration of the vehicle.

Abstract: A traction control system for a vehicle reduces the rate of slip of driving wheels of the vehicle by reducing the traction force transmitted to the road surface from the driving wheels when the driving wheels slip. Whether the vehicle is making a turn is judged, and whether the vehicle is in an instable state which occurs when the vehicle is making a turn. The traction force is reduced by a higher rate when the driving wheels slip while the vehicle is making a turn than when the driving wheels slip while the vehicle is running straight, and the traction force is reduced by a higher rate when the driving wheels slip while the vehicle is in an instable state than when the driving wheels slip while the vehicle is making a turn.