Kyosho Super Stock 20

This is a Kyosho Super Stock 20 motor what means there was a timing of 20 degrees used at this motor. There had been other Super Stock motors as well, using 24 or 36 degrees timing advance. But the 20 degree version seems the oldest.
All of these Stock versions came with the clamped endbell. But there was also a modified version of this can with removable endbell.
These new tear-downs were used also by other companies for making their own motors, one of them being Trinity.