1991 Corvette Identification Numbers

Below is a listing of common identification numbers and ways of identifying a 1991 Corvette L98 and ZR-1.

VIN Tag Information
Base:  1G1YY238XM5100001 - 1G1YY238XM5118595
ZR-1: 1G1YZ23JXM5800001 - 1G1YZ23JXM5802044
Digit Definition
1st Nation of Origin:  1 = U.S.
2nd Manufacturer:  G = GM
3rd Make and Type:  1 = Chevrolet Passenger
4th Carline:  Y = Corvette
5th Carline/Series:  Y = Corvette, Z = ZR-1
6th Body Type:  2 = Coupe Hatchback, 3 = Convertible
7th Restraint System:  1 = Manual Belts, 3 = Manual Belts/Driver Air Bag
8th Engine:  8 = L98, J = LT5
9th Check digit to verify VIN correctly recorded.
10th Model Year:  M = 1991
11th Assembly Plant:  5 = Bowling Green, KY
Last 6 digits Production Number starting with 100001 and up for the base model and 800001 and up for the ZR-1.

Engine Suffix ID Numbers
ZTA: 350ci, 245hp / 250hp, (automatic transmission)
ZTB: 350ci, 245hp / 250hp, (manual transmission, oil cooler)
ZTC: 350ci, 245hp / 250hp, (automatic transmission, oil cooler)
ZTK: 350ci, 375hp
Callaway (RPO B2K): Chevrolet engine coding was replaced as follows:
1st two digits:  model year
Next three digits:  Callaway sequence number
Last four digits:  last four digits of vehicle identification number

Block ID Numbers
10153558: 350ci, 375hp
14093638: 350ci, 245hp / 250hp

Head ID Numbers
10088113: 350ci, 245hp / 250hp
10174389: 350ci, 375hp (left hand)
10174390: 350ci, 375hp (right hand)