Holley Date Codes



Four Digit Date Codes
First Three Digits--Day of Year
Day Code
Non Leap Year
Day Code
Leap Year
Month of
Production
001-031001-031January
032-059032-060February
060-090061-091March
091-120092-121April
121-151122-152May
152-181153-182June
182-212183-213July
213-243214-244August
244-273245-274September
274-304275-305October
305-334306-335November
335-365336-366December

Fourth Digit--Year
11961/1971/1981/1991
21962/1972/1982/1992
31963/1973/1983/1993
41964/1974/1984/1994
51965/1975/1985/1995
61966/1976/1986/1996
71967/1977/1987/1997
81968/1978/1988/1998
91969/1979/1989/1999
01970/1980/1990/2000

Three Digit Date Codes
First Digit--Year
11961/1971
21962/1972
31963
41964
51965
61966
71967
81968
91969
01970

Second Digit--Month
1January
2February
3March
4April
5May
6June
7July
8August
9September
0October
ANovember
BDecember

Third Digit--Week
1First Week
2Second Week
3Third Week
4Fourth Week
5Fifth Week