What year is a 350 Chevy engine with casting number 3970010 and 010 WR G18 on the front of timing chain side?

The casting number 3970010 for a 350 Chevy small-block engine indicates it was produced in 1969. The additional markings 010 WR G18 are further details related to the specific engine's production date and plant. While they don't directly give a year, they are consistent with a 1969 production date given the casting number.