O im sorry i forgot to mention that what I posted before is about JDM B16A motors, the one that say B16A only, and not B16A2 or B16A3 which are the USDM versions, but the part about the year stamp on the head is still the same, but this only works for the head, since the head can be taken off easily it is possible for you to have an older/newer bottom end than the head, but if you know that they have not been seperated then u know the year the motor was made