What year is a 350 Chevy engine with casting no 3970010 and 13w221249?
The casting number 3970010 indicates a 350 cubic inch Chevrolet small-block engine. However, that casting number alone doesn't tell you the year. It only tells you the basic block design.
The number 13W221249 is the engine's serial number. The "13" portion is the most important part for dating. It indicates the engine was manufactured in 1973. The "W" represents the plant where it was made.
