🏷️ Basic Information

Make:

Chevrolet

Model:

Corvette

Year:

1981

Engine Code Primary:

LG4 (305 CID V8)

Engine Code Optional:

L81 (350 CID V8)

Chassis Code:

C3

👋 Introduction

Positioning:

The 1981 Corvette represented Chevrolet's flagship sports car, a blend of performance and evolving technology within the iconic C3 generation. This manual caters to enthusiasts and professional mechanics maintaining this specific model year.

Competitors:

Competed with European sports cars like Porsche 924/944, Jaguar XJ-S, and domestic offerings like the Datsun 280ZX.

Vehicle Highlights:

Targa top, fiberglass body, advanced for its time engine management (Cross-Fire Injection on L81), independent suspension.

Manual Value:

Essential resource for accurate diagnostics, maintenance, and repairs, preserving the originality and performance of a classic Corvette.

📋 Manual Details

Coverage Scope:

All Models/Engines/Trim/Transmissions Types

Estimated Page Count:

Approximately 1500-2000 pages (typical for comprehensive workshop manuals)

Type:

Workshop Repair Service Manual

Language:

English

Format:

PDF Download

📖 Manual Coverage

Engine:

305 V8 (LG4), 350 V8 (L81), including: fuel injection (Cross-Fire Injection for L81), ignition, cooling, lubrication, emission controls, engine mechanical (disassembly, assembly, specifications)

Transmission:

Automatic (THM-200-4R), Manual (4-speed), including: overhaul, adjustments, troubleshooting, fluid specifications

Drivetrain:

Rear axle assembly, driveshaft, universal joints, CV joints (if applicable to specific configurations)

Suspension:

Front (independent, unequal-length A-arms, coil springs), Rear (independent, trailing arms, transverse leaf spring), including: alignment specifications, component replacement, shock absorbers, bushings

Brakes:

Front disc (ventilated), Rear disc, including: hydraulic system, power assist, parking brake, specifications, wear limits

Steering:

Power steering, steering column, linkage, including: overhaul, fluid specifications, troubleshooting

Electrical:

Starting system, charging system, battery, lighting, instrumentation, power windows, power door locks, wipers, horn, radio, fuse/relay locations, wiring diagrams

Fuel System:

Fuel tank, fuel pump, fuel lines, fuel filters, carburetor (for 305), fuel injection (for 350), troubleshooting

Exhaust System:

Exhaust manifolds, catalytic converter, mufflers, tailpipes

Cooling System:

Radiator, fan (mechanical/electric), water pump, thermostat, coolant specifications, pressure testing

Body And Interior:

Body panels, doors, hood, trunk, bumpers, glass, trim, seats, dashboard, carpeting, sound insulation

Maintenance:

Oil changes, filter replacements, fluid checks and changes, lubrication, tune-ups, spark plug replacement, belt inspection/replacement, brake pad replacement, tire rotation

Troubleshooting:

System diagnostics, fault finding for engine, electrical, transmission, brake, and other systems

Repair:

Component disassembly, inspection, repair, and reassembly for all major systems, including engine rebuild procedures, transmission overhaul, suspension component replacement, brake caliper overhaul

Specifications:

Torque specifications, clearances, dimensions, fluid capacities, alignment settings, electrical resistance values

Wiring Diagrams:

Detailed electrical system wiring schematics for all vehicle circuits

Depth:

Comprehensive - covers basic maintenance through to major component overhauls and advanced diagnostics

📊 Manual Specifications

File Type:

PDF

Searchability:

Searchable text (typical for high-quality PDFs)

Printability:

Printable pages

Quality:

High-resolution scans of original factory documentation

Binding:

N/A (Digital PDF download)

Paper Type:

N/A (Digital PDF download)

⚙️ Engine Specifications

Engine Name Standard:

305 V8 (LG4)

Displacement Standard:

305 cubic inches (5.0 Liters)

Horsepower Standard:

175 hp @ 4,200 rpm

Torque Standard:

230 lb-ft @ 3,200 rpm

Engine Name Optional:

350 V8 (L81) - Cross-Fire Injection

Displacement Optional:

350 cubic inches (5.7 Liters)

Horsepower Optional:

190 hp @ 4,800 rpm

Torque Optional:

240 lb-ft @ 3,200 rpm

Fuel Delivery Standard:

Rochester Quadrajet 4-barrel carburetor

Fuel Delivery Optional:

Bosch/AC-Delco L-Jetronic based Cross-Fire fuel injection

Fuel Type:

Unleaded gasoline, premium recommended

Ignition Type:

Electronic ignition (HEI distributor)

🔧 Transmission

Transmission Type Standard:

3-Speed Automatic (THM-200-4R for L81/optional for LG4)

Transmission Type Optional:

4-Speed Manual (M20/M21 variants, less common)

Overdrive Gear:

THM-200-4R features an overdrive gear for improved fuel economy.

Automatic Transmission Fluid:

Dexron III (or equivalent)

Manual Transmission Fluid:

GL-4 Gear Oil (e.g., SAE 80W-90)

📐 Dimensions

Length:

185.4 inches

Width:

72.8 inches

Height:

47.8 inches

Wheelbase:

98.0 inches

Curb Weight Approximate:

3,400 - 3,500 lbs

Gross Vehicle Weight Rating:

Approximately 4,200 lbs

Trunk Volume Approximate:

10.6 cubic feet

Track Width Front:

61.0 inches

Track Width Rear:

61.7 inches

Ground Clearance:

Approximately 4.5 - 5.0 inches

🛡️ Safety Features

NHTSA Ratings:

N/A - NHTSA ratings were not standardized for this era.

Active Safety Features:

Power front disc brakes, power steering, rear-wheel drive.

Passive Safety Features:

3-point seat belts, padded interior surfaces, collapsible steering column.

💡 Technology Features

Infotainment System:

Standard AM/FM radio, optional cassette player. Analog gauges for speedometer, tachometer, fuel level, engine temperature, oil pressure, voltmeter.

Driver Assistance Features:

Limited to power steering and power brakes. No modern electronic driver aids.

Connectivity:

No external connectivity features (e.g., Bluetooth, USB).

Comfort Features:

Optional air conditioning, power windows, power door locks, tilt-telescopic steering wheel.

🔧 Maintenance

Oil Change Interval:

Every 3,000 miles or 6 months, whichever comes first (conventional oil).

Transmission Fluid Change:

Every 24,000-36,000 miles or 24 months.

Spark Plug Replacement:

Approximately 30,000 miles.

Engine Oil Type:

API SF, SAE 10W-30 or 10W-40 recommended (consult manual for specific ambient temperature ranges).

Coolant Type:

Ethylene glycol-based antifreeze, 50/50 mix with distilled water.

Brake Fluid Type:

DOT 3 brake fluid.

Power Steering Fluid:

GM Type A Suffix A or Dexron II (or equivalent).

Common Problems:

C3 Corvettes of this era can experience issues with aging electrical components, fiberglass delamination, vacuum hose deterioration, and potential wear on suspension bushings. Carburetor and early fuel injection systems may require meticulous tuning.

Clutch Slave Cylinder Leak:

Hydraulic clutch systems can develop leaks over time (for manual transmission models).

Rear Leaf Spring Sags:

The composite transverse leaf spring can sag over many years, affecting ride height.

📚 Vehicle History

Chevrolet Legacy:

Chevrolet has a long history of performance vehicles, with the Corvette being its halo sports car since 1953.

C3 Generation:

The 1981 Corvette is part of the third generation (C3) of the Corvette, which ran from 1968 to 1982. This year saw refinements and the introduction of the Cross-Fire Injection system.

Production Location:

Bowling Green, Kentucky, USA

Production Numbers 1981:

Approximately 40,600 units produced for the 1981 model year.

🏆 Awards & Recognition

Vehicle Recognitions:

While specific awards for the 1981 model year are not widely documented, the C3 Corvette as a generation is an automotive icon, consistently recognized for its design and performance in its era.