1971 Corvette Identification Numbers

Below is a listing of identification numbers for the 1971 Corvette including engine block, head id, casting numbers and more.

VIN Tag Information
194371S100001 - 194371S121801 (coupe)
194671S100001 - 194671S121801 (convertible)
Digit Definition
1st Division:  1 = Chevrolet
2nd / 3rd Series:  94 = Corvette
4th/5th Body Style:  37 = 2-door coupe, 67 = 2-door convertible
6th Model Year:  1 = 1971
7th Assembly Plant:  S = St. Louis, MO.
Last 6 digits Production Number starting with 100001 - 121801

Engine Suffix ID Numbers
CGT: 350ci, 270hp (automatic transmission)
CGY: 350ci, 330hp (manual transmission, ZR1)
CGZ: 350ci, 330hp (manual transmission, LT1)
CJK: 350ci, 270hp (automatic transmission)
CJL: 350ci, 270hp (manual transmission)
CPH: 454ci, 365hp (manual transmission)
CPJ: 454ci, 365hp (automatic transmission)
CPW: 454ci, 425hp (aluminum heads, manual transmission)
CPX: 454ci, 425hp (aluminum heads, automatic transmission)

Block ID Numbers
3970010: 350ci, 270hp, 330hp
3963512: 454ci, 365hp, 425hp

Head ID Numbers
3946074: 454ci, 425hp
3973487: 350ci, 270hp, 330hp
3993820: 454ci, 365hp
3994026: 454ci, 425hp (uncertain use)

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

Two main plants were casting Chevrolet engine parts during 1970: Flint, Michigan and Tonawanda, New York.

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

Carburetor ID Numbers
Rochester Q-jet #7041204: 454ci, 365hp (automatic transmission)
Rochester Q-jet #7041205: 454ci, 365hp (manual transmission)
Rochester Q-jet #7041212: 350ci, 270hp (automatic transmission)
Rochester Q-jet #7041213: 350ci, 2790hp (manual transmission)
Holley R4801A #3989021: 350ci, 330hp (manual transmission)
Holley R4802A #3986195: 454ci, 425hp (manual transmission)
Holley R4803A #3986196: 454ci, 425hp (automatic transmission)

Distributor ID Numbers
1112038: 350ci, 330hp (transistor ignition)
1112050: 350ci, 270hp
1112051: 454ci, 365hp
1112053: 454ci, 425hp (automatic transmission, transistor ignition)
1112076: 454ci, 425hp (manual transmission, transistor ignition)

Alternator ID Numbers
1100543: 454ci, 365hp, 425hp
1100950: 350ci, 270hp, 330hp
1100544: All with air conditioning.

Trim Tag and Location:

1971 Corvette Trim Tag Location 1971 Corvette Trim Tag