Below is a listing of common identification numbers for the 1974 Corvette including engine block, head id, casting numbers and more.
Vehicle Identification Number |
1Z37J4S400001 - 1Z37J4S440606 |
Digit |
Definition |
1st |
1 = GM Division = Chevrolet |
2nd |
Z = Series = Corvette |
3rd/4th |
Body Style: 37 = Coupe, 67 = Convert |
5th |
Engine Type: J = L48, T = L82, Z = LS4 |
6th |
4 = Model Year = 1974 |
7th |
Assembly Plant: S = St. Louis, MO. |
Last 6 digits |
Production Number starting with 400001 and up. |
Engine Suffix ID Numbers |
CKZ: |
350ci, 195hp, (manual transmission) |
CLA: |
350ci, 195hp, (automatic transmission) |
CLB: |
350ci, 195hp, (manual transmission, California emissions) |
CLC: |
350ci, 195hp, (automatic transmission, California emissions) |
CLD: |
350ci, 250hp, (automatic transmission) |
CLH: |
350ci, 250hp, (automatic transmission, California emissions) |
CLR: |
350ci, 250hp, (manual transmission) |
CLS: |
350ci, 250hp (California emissions, manual transmission) |
CWM: |
454ci, 270hp (manual transmission) |
CWR: |
454ci, 270hp (automatic transmission) |
CWS: |
454ci, 270hp, (automatic transmission, California emissions) |
CWT: |
454ci, 270hp, (California emissions, manual transmission) |
Block ID Numbers |
3970010: |
350ci, 195hp, 250hp |
3999289: |
454ci, 270hp |
Head ID Numbers |
333882: |
350ci, 195hp, 250hp |
336781: |
454ci, 270hp |
Carburetor ID Numbers |
Rochester Q-jet #7044221: |
454ci, 270hp (manual transmission) |
Rochester Q-jet #7044206: |
350ci, 195hp (automatic transmission) |
Rochester Q-jet #7044207: |
350ci, 195hp (manual transmission) |
Rochester Q-jet #70445210: |
350ci, 250hp (automatic transmission) |
Rochester Q-jet #7044211: |
350ci, 250hp (manual transmission) |
Rochester Q-jet #7044225: |
454ci, 270hp (automatic transmission) |
Rochester Q-jet #7044505: |
454ci, 270hp (automatic transmission, California emissions) |
Rochester Q-jet #7044506: |
350ci, 250hp (automatic transmission, California emissions) |
Rochester Q-jet #7044507: |
350ci, 250hp (California emissions, manual transmission) |
Cylinder Head Casting Number:
The cylinder head casting number is usually found on top of the cylinder head in between two valves and the rocker arm studs.
Cylinder Head Casting Date:
The cylinder head casting date is usually found adjacent to the cylinder head casting number. The casting date code is an alphanumeric sequenced number. The first digit is usually a letter which specifies the month that the block was cast. Some casting dates have been found with all digits being numbers, the first of which corresponds to the month.
Cylinder Head Casting Number Month Codes (1st Digit) |
A - January |
E - May |
I - September |
B - February |
F - June |
J - October |
C - March |
G - July |
K - November |
D - April |
H - August |
L - December |
Example: Flint Cylinder Head Casting Number - D 19 9
- D: Month = April
- 19: Casting Day = 19th
- 9: Casting Year = 1959
Example: Tonawanda Cylinder Head Casting Number - D 19 59
- D: Month = April
- 19: Casting Day = 19th
- 59: Casting Year = 1959
Distributor ID Numbers |
1112114: |
454ci, 270hp |
1112150: |
350ci, 250hp |
1112247: |
350ci, 195hp |
1112544: |
350ci, 195hp (California emissions, manual transmission) |
1112850: |
350ci, 195hp (California emissions, manual transmission) |
1112851: |
350ci, 195hp (automatic transmission, California emissions) |
1112853: |
350ci, 250hp (automatic transmission) |
Alternator ID Numbers |
1100544: |
All engines with air conditioning. |
1100950: |
All engines without air conditioning. |