🏷️ Basic Information

Make:

Chevrolet

Model:

Corvette

Year:

1978

Engine Designation:

454 Big-Block V8

Chassis Code:

C3

👋 Introduction

Positioning:

The 1978 Corvette represented a significant year for the C3 generation, offering potent performance with the available 454 Big-Block. This manual serves enthusiasts and owners looking to maintain and restore these iconic muscle cars.

Competition:

Competed with other performance-oriented grand tourers and sports cars of the era, such as the Ford Mustang Cobra, Pontiac Firebird Trans Am, and various European sports cars. The 454 engine option positioned it at the higher end of domestic performance.

Features Vehicle:

Removable T-tops, aerodynamic styling, powerful V8 engine options, independent suspension, and a focus on performance driving.

Features Manual:

Comprehensive, factory-authorized repair procedures, detailed schematics, troubleshooting guides, and essential technical data for accurate servicing.

📋 Manual Details

Coverage:

Complete factory service and repair information for the 1978 Chevrolet Corvette equipped with the 454 V8 engine. Covers all mechanical, electrical, and body systems.

Pages:

Hundreds of pages (exact count not specified, but implied to be comprehensive)

Type:

Factory Service Repair Manual

Language:

English

Format:

Downloadable PDF

📖 Manual Coverage

Engine:

454 V8 (LS4 designation), including disassembly, assembly, diagnostics, troubleshooting, and specifications for major components (block, heads, crankshaft, pistons, camshaft, valvetrain, cooling system, lubrication system).

Fuel System:

Carburetion (Quadrajet 4-barrel), fuel pump, fuel lines, fuel tank, emissions control systems relevant to the 1978 model year.

Ignition System:

Distributor, spark plugs, ignition wires, ignition timing, electronic spark control (if applicable).

Transmission:

THM400 (Turbo Hydra-Matic 400) automatic transmission, including removal, installation, internal repairs, torque converter, and fluid specifications.

Drivetrain:

Driveshaft, universal joints, rear axle assembly (differential, half-shafts), lubrication.

Suspension:

Front independent suspension (upper and lower control arms, ball joints, coil springs, shock absorbers), rear independent suspension (springs, control arms, shock absorbers), wheel alignment specifications.

Steering:

Power steering system (pump, hoses, steering gear), steering column, steering wheel removal and installation.

Brakes:

Front and rear disc brakes, hydraulic system, master cylinder, brake calipers, brake lines, parking brake system, fluid specifications.

Electrical System:

Wiring diagrams, battery, charging system (alternator, voltage regulator), starting system (starter motor, solenoid), lighting system (headlights, taillights, interior lights), instrument cluster, gauges, switches, relays, fuses, power windows, power door locks (if equipped).

Body And Frame:

Chassis lubrication, body panel removal and installation, door hardware, hood, glass, bumpers, weatherstripping, frame inspection and repair.

HVAC:

Heating and air conditioning system components, operation, and service procedures.

Maintenance:

Scheduled maintenance, oil changes, filter replacements, fluid checks and changes, lubrication points, tune-up procedures, belt inspections and replacement.

Troubleshooting:

Diagnostic charts and procedures for identifying and resolving common problems across all major systems.

Repair:

Detailed step-by-step repair instructions for component disassembly, reassembly, and replacement, including torque specifications and special tool requirements.

Diagnostics:

Diagnostic flowcharts, component testing procedures, and symptom-based troubleshooting.

Specifications:

Comprehensive technical specifications for all systems, including tolerances, clearances, torque values, fluid capacities, and electrical resistance.

Depth:

In-depth coverage suitable for professional mechanics and experienced DIY enthusiasts. Includes detailed diagrams, exploded views, and torque specifications for complete overhauls and complex repairs.

📊 Manual Specifications

File Type:

PDF (Portable Document Format)

Quality:

High-resolution scans of original factory documentation, allowing for clear printing of text and diagrams.

Binding:

N/A (Digital download - printable)

Paper:

N/A (Digital download - printable on user's choice of paper)

⚙️ Engine Specifications

Engine Code:

LS4

Displacement:

454 cubic inches (7.4 Liters)

Configuration:

V8, Overhead Valve (OHV)

Bore X Stroke:

4.25 in x 4.00 in (108 mm x 101.6 mm)

Compression Ratio:

8.5:1

Horsepower:

250 hp @ 4000 rpm (SAE Net)

Torque:

395 lb-ft @ 3200 rpm (SAE Net)

Carburetor:

Rochester Quadrajet 4-barrel (Model 17058210, 17058212, etc. - specific number varies by build date/emission requirements)

Fuel Type:

Unleaded gasoline, 91 octane (minimum recommended)

Ignition System:

High-energy electronic ignition (HEI) distributor

Coolant Capacity:

22 quarts (20.8 Liters) with heater

Oil Capacity:

5 quarts (4.7 Liters) with filter

Recommended Oil Viscosity:

10W-40 or 10W-30 (depending on climate and manufacturer recommendation)

🔧 Transmission

Type:

Turbo Hydra-Matic 400 (THM400)

Gear Ratios:

1st: 2.48, 2nd: 1.48, 3rd: 1.00, Reverse: 2.08

Type:

None for 454 engine option in 1978

Fluid Type:

Dexron III Automatic Transmission Fluid (ATF) - Note: Original spec was Dexron II, but Dexron III is backward compatible and recommended for newer fluid properties.

Fluid Capacity:

5 quarts (4.7 Liters) dry fill, 11 quarts (10.4 Liters) total capacity

📐 Dimensions

Length:

182.5 inches (4635.5 mm)

Width:

70.8 inches (1798.3 mm)

Height:

47.8 inches (1214.1 mm)

Wheelbase:

98.0 inches (2489.2 mm)

Curb Weight:

Approximately 3500-3650 lbs (1588-1656 kg), depending on options

🛡️ Safety Features

Federal Safety Standards:

Compliant with all applicable U.S. Federal Motor Vehicle Safety Standards (FMVSS) for 1978.

Braking System:

Power-assisted, four-wheel disc brakes.

Steering System:

Power steering.

Seat Belts:

Three-point lap and shoulder belts (standard).

Rollover Protection:

Reinforced windshield frame and integral roll bar behind the seats.

💡 Technology Features

Audio System:

Optional AM/FM radio, AM/FM stereo, or AM/FM stereo with cassette player. Typically 4 speakers (two front, two rear).

Cruise Control:

Optional cruise control system.

Connectivity Features:

None by modern standards; primarily analog systems and basic power accessories.

🔧 Maintenance

Oil Change:

Every 3,000 miles or 6 months, whichever comes first.

Transmission Fluid Change:

Every 24,000 miles or 24 months.

Spark Plug Replacement:

Every 30,000 miles.

Coolant Flush:

Every 30,000 miles or 24 months.

Engine Oil Spec:

API SF/CD or SG/CD rated oils. Viscosity 10W-30 or 10W-40 recommended.

Brake Fluid Spec:

DOT 3 heavy-duty hydraulic brake fluid.

Common Problems:

Carburetor tuning and adjustment (Quadrajet), vacuum leaks, aging rubber and plastic components (hoses, seals, bushings), electrical connector corrosion, suspension wear, potential for rear main seal leaks on the 454. The fiberglass body can be prone to cracking around mounting points.

Emissions Controls:

Specific to 1978 regulations, including catalytic converter, air injection system, and EGR valve. Proper functioning is crucial for performance and legality.

📚 Vehicle History

Heritage:

Chevrolet has a long history of performance vehicles, with the Corvette being its flagship sports car since its introduction in 1953. Known for V8 power and sporty design.

Evolution:

The 1978 model year marked the 25th anniversary of the Corvette. It featured a revised interior and exterior, with the introduction of the pace car edition for the Indy 500. The 454 engine was a carryover performance option from previous years.

Production Years:

C3 generation: 1968-1982. 1978 model year production: 40,030 units (across all configurations).

Manufacturing Location:

St. Louis, Missouri, USA (until 1981), Bowling Green, Kentucky, USA (from 1981 onwards).

🏆 Awards & Recognition

Historical Significance:

Recognized as a classic American sports car with enduring appeal, particularly the Big-Block variants which are highly sought after by collectors and performance enthusiasts.

Collectibility Index:

Consistently ranks high in classic car valuations, especially for well-maintained examples with desirable options like the 454 engine.