Chevrolet Corvette Service Repair Manuals

1981 CORVETTE

INDEX
CHASSIS
ENGINE
HISTORY
ID
LITERATURE
OPTIONS
PHOTOS
1982

Probably the most significant change this year was hidden from view.
Corvettes with Turbo HydraMatic had a new fiberglass-reinforced monoleaf rear spring that weighed just eight pounds (33 pounds less than the multi-leaf steel spring it replaced).
The new spring eliminated interleaf friction.
Manual-shift models kept the old spring, as did those with optional Gymkhana suspension.
Side door glass was made even thinner again, in a further attempt to cut overall car weight.
A new L81 version of the 350-cid V-8 arrived this year.
It was rated for 190 hp, with lightweight magnesium rocker arm covers.
New stainless-steel free-flowing exhaust manifolds weighed 14 pounds less than the previous cast iron manifolds.
A new thermostatically-controlled auxiliary electric fan boosted cooling and allowed use of a smaller main fan.
The engine air cleaner had a new chromed cover.
A new Computer Command Control system controlled fuel metering, as well as the torque converter lock-up clutch that operated in second and third gears.
Manual transmission was available in all 50 states.
It was the first time in several years that buyers of Corvettes sold in California could order a stick shift.
A quartz crystal clock was now standard.
The Corvette's standard anti-theft alarm added a starter-interrupt device.
Joining the option list was a six-way power seat.
Electronic-tuning radios could have built-in cassette or 8-track tape players or a CB transceiver.
The Corvette's ample standard equipment list included
- either four-speed manual or automatic transmission (same price)
- four-wheel power disc brakes
- limited-slip differential
- power steering
- tinted glass
- twin remote-control sport mirrors
- concealed two-speed wipers
- halogen high-beam retractable headlamps
- air conditioning
- power windows
- a tilt-telescope leather-wrapped steering wheel
- a tachometer
- an AM/FM radio
- a trip odometer
- courtesy lights
- a luggage compartment security shade
Corvette buyers had a choice of cloth-and-vinyl or leather-and-vinyl upholstery.
Corvettes rode on P225/70R-15 steel-belted radial blackwall tires on 15 x 8 inch wheels.
The optional Gymkhana suspension (price $54) was also included with the trailer towing package.
Body colors this year were
- Mahogany Metallic
- White
- Silver Metallic
- Black
- Bright Blue Metallic
- Dark Blue Metallic
- Yellow
- Beige
- Red
- Maroon Metallic
- Charcoal Metallic
Four two-tone combinations were available:
- Silver and Dark Blue
- Silver and Charcoal
- Beige and Dark Bronze
- Autumn Red and Dark Claret
All two-tone cars were painted at the new plant in Bowling Green, Kentucky.
Interiors came in Silver Gray; Charcoal; Dark Blue; Camel; Dark Red; and Medium Red.

V.I.N. NUMBERS

The serial number [Vehicle Identification Number -- VIN] was stamped on a plate on the inner vertical surface of the left windshield pillar visible through the windshield.
The St. Louis Assembly Plant Serial numbers ranged from 1G1AY87*4BS400001 to 1G1AY87*4BS431611
The Bowling Green Assembly Plant Serial numbers ranged from 1G1AY87*4B5100001 to 1G1AY87*4B5108995

Position	Character	Description
1	1	US built
2	G	General Motors product
3	1	Chevrolet Motor Division vehicle
4	A	Type of non-passive passenger restraint system
5	Y	Corvette car line series
6 & 7	87	Body style number: two-door plainback special coupe
8	*	Engine type where * is replaced by the following 6 = L82 350-cid V8, 230-hp
9	?	A check digit that calculates the characters in the serial number and gives it a single digit code and can be used to verify that the serial number is legitimate
10	B	The model year where B = 1981
11	S or 5	S=St. Louis, MO and 5=Bowling Green, KY
12-17	100001 and up	production sequence

Engine serial number began 0001001
Corvette engines have the last six digits of the VIN stamped on the block just ahead of the cylinder head on the right-hand side combined with a three-letter engine code suffix
Also cast into the top rear of the block is a four-symbol code indicating when the engine was built
- The first letter of the date code shows the month the block was cast
- The one or two numbers shows the month
- The last digit shows the year
Engine suffixes:

Code	Engine	Horsepower	Compression	Transmission	Fuel Supply	Emission Control System
ZDA	L81 350-cid	190-hp V-8	8.2:1	manual	four-barrel carburetor
ZDB	L81 350-cid	190-hp V-8	8.2:1	automatic	four-barrel carburetor	California
ZDC	L81 350-cid	190-hp V-8	8.2:1	manual	four-barrel carburetor	California
ZDD	L81 350-cid	190-hp V-8	8.2:1	automatic	four-barrel carburetor

The 1981 Corvette exterior colors were:
- 06 = Mahogany Metallic
- 10 = White
- 13 = Silver Metallic
- 19 = Black
- 24 = Bright Blue Metallic
- 28 = Dark Blue Metallic
- 52 = Yellow
- 59 = Beige
- 75 = Red
- 79 = Maroon Metallic
- 84 = Charcoal Metallic
- 33/38 = Silver and Dark Blue
- 33/39 = Silver and Charcoal
- 50/74 = Beige and Dark Bronze
- 80/98 = Autumn Red and Dark Claret.
Upholstery Codes

Color	Cloth & Leather Upholstery	Leather Upholstery
Charcoal	19C	192
Dark Blue	29C	292
Camel	64C	642
Dark Red	67C	672
Silver Gray		152
Medium Red		752

IDENTIFICATION

Model No.	Body/Style No.	Body Type	Factory Price	Shipping Weight	Production Total
1Y	Z87	2-dr. Sport Coupe - 2 passenger	$15,248	3179	40,606

ENGINE

Feature	Standard Engine (RPO L81)
Type	V-8, 90-degree Overhead valve
Block	Cast iron block
Displacement	350 cid (5.7 liters)
Bore & Stroke	4.00 x 3.48"
Compression ratio	8.2:1
Brake horsepower	190 @ 4200
Torque	280 lb-ft @ 1600
Main bearing	five
Valve lifters	hydraulic
Fuel supply	Rochester Quadrajet

TRANSMISSION

Standard Manual Transmission
- four-speed fully-synchronized
- floor-mounted gear shifter
- gear ratios
  - 1st = 2.88:1
  - 2nd = 1.91:1
  - 3rd = 1.33:1
  - 4th = 1.00:1
  - Rev = 2.78:1
- Final drive ratio: 2.72:1
Automatic Transmission
- Three-speed Turbo Hydra-Matic
- floor-mounted gear shifter
- gear ratios
  - 1st = 2.52:1
  - 2nd = 1.52:1
  - 3rd = 1.00:1
  - Rev = 1.93:1
- Final drive ratio: 2.87:1

CHASSIS

Feature	Coupe
Wheelbase	98 inches (2.489 m)
Overall length	185.2 inches (4.704 m)
Overall width	69.0 inches (1.753 m)
Overall height	48 inches (1.219 m)
Ground Clearance	4.5 inches (11.4 cm)
Front tread	58.7 inches (1.491 m)
Rear tread	59.5 inches (1.511 m)
Wheel size	15 x 8 inches
Tires	P225/70R-15 SBR (steel-belted radial)
Positraction	standard
Steering	recirculating ball
Front suspension	Independent, unequal-length control arms with ball joints, coil springs, and stabilizer bar
Rear suspension	Independent, trailing link, transverse semi-elliptic leaf springs
Brakes	Hydraulic, vented four wheel discs; 11.75-inch diameter, single calipers
Ignition	HEI electronic
Body construction	Separate fiberglass body and box-type ladder frame with cross-members
Fuel tank	24 US Gal (20 Imp Gal) (91 liters)

OPTIONS

RPO AU3	Power door locks	$145
RPO A42	Power driver seat	$183
RPO CC1	Removable glass roof panels	$414
RPO C49	Rear window defogger	$119
RPO DG7	Electric sport mirrors	$117
RPO D84	Two-tone paint	$399
RPO FE7	Gymkhana suspension	$57
RPO F51	Heavy-duty shock absorbers	$37
RPO G92	Performance axle ratio	$20
RPO K35	Cruise control	$155
RPO MM4	Four-speed manual transmission	no cost option
RPO N90	Four aluminum wheels	$428
RPO QGR	P255/70R-15 Raised-white-letter steel-belted radial tires	$72
RPO QXH	P255/60R-15 Raised white-letter steel-belted radial tires	$491.92
RPO UL5	Radio delete	$118 credit
RPO UM4	AM-FM electronic tuning stereo radio with 8-track tape system	$386
RPO UMS	AM-FM electronic tuning stereo radio with 8-track tape and CB system	$712
RPO UM6	AM-FM electronic tuning stereo radio with cassette	$423
RPO UN5	AM-FM electronic tuning stereo radio with cassette and CB system	$750
RPO U58	AM-FM stereo radio	$95
RPO U75	Power antenna	$55
RPO V54	Roof panel carrier	$135
RPO YFS	California emissions certification	$46
RPO ZN1	Trailering package	$110

HISTORICAL NOTES

1981 Corvette Notes

Introduced: September 25,1980. Model-year production: 40,606 (but Chevrolet first reported a total of 40,593 units).
Calendar-year production: 27,990.
Model-year sales by U.S. dealers: 33,414.
Of the total output this model year, 8,995 Corvettes came out of the new plant at Bowling Green, Kentucky, which began production in June 1981.
Despite some weak years in the industry, Corvette sales remained strong through this period.