what is this vacuum valve for?

[nvrbdn]

found a vacuum valve in the garage today while cleaning the work bench up. the line going out by itself says to dist.the bottom one on other side says carb, and the top says delay. part # 14036771 the side to carb can suck, but not blow, you can blow and suck air through the dist vent, and the delay allows air both ways, just slowly with resistance. thanks.

[nascarxx29]

spark advance distributor delay valve.From carb port vacuum