1966 Buick Riviera Gran Sport

Personal luxury powered by 1966 MW 425 Wildcat V8.

Black 1966 Riviera Gran Sport, front three-quarter view

Engine MW 425, 340 gross hp

Induction Single Quadrajet

Rear axle 3.42 positive traction

Wheelbase 119 inches

GS production 5,718

Story

1966 Buick Riviera Gran Sport

The redesigned 1966 Riviera made the 340-hp 425 standard across the line. Gran Sport value came from the 3.42 positive-traction axle, high-performance springs and shocks, chrome engine dress, and package identity—not a different standard engine.

The dual-quad distinction

Buick offered dealer-installed Super Wildcat equipment, but dual quads were not standard 1966 GS content. Preserve that distinction when evaluating a car.

**Black 1966 Riviera Gran Sport, side view**BrokenSphere via Wikimedia Commons · CC BY-SA 3.0

Price history

Values

Nominal dollars from original price sheets, auction archives, and approved value references.

Original Price

Base MSRP $4,424

Riviera sport coupe base price (1966)

Personal Luxury Powerhouse: 1966 Buick Riviera GS
Option price $177

A9 Riviera Gran Sport High Performance Group (1966)

Personal Luxury Powerhouse: 1966 Buick Riviera GS
Other price $4,690

Integrated Riviera Gran Sport MSRP reported by J.D. Power (1966)

1966 Buick Riviera Gran Sport 2 Door Hardtop values

Market Observations

Price guide value $23,100

Jul 31, 2026 · Hagerty Valuation Tools · Current guide point
July 2026 condition #3 guide for the 1966 Riviera Gran Sport two-door Sport Coupe with the 425cid/340hp four-barrel V8 · unknown · good Exact year, package, body, and standard-engine guide benchmark. Documentation, Super Wildcat equipment, options, originality, and individual-car condition still require separate normalization; locked guide grades are not inferred.
1966 Buick Riviera Gran Sport valuation
Auction sale $44,000

Jun 23, 2026 · Bring a Trailer
Riviera GS chassis 494876H959830 represented with the 360-hp dual-four-barrel Super Wildcat 425 and three-speed automatic · survivor · unknown Completed vehicle-specific sale at the venue-published winning bid. The listing represents factory dual-quad equipment and shows engine and body identifiers, while reviewed model-level sources disagree over factory versus dealer installation; individual-car paperwork remains required. Tires, suspension bushings, carburetor service, nonworking clock and radio, and true-mileage-unknown status remain explicit.
1966 Buick Riviera GS Super Wildcat chassis 494876H959830
Auction sale $46,000

Jan 12, 2026 · Hemmings Auctions via CLASSIC.COM
Riviera GS chassis 494876H954963, 7k miles TMU, automatic, classified as original or highly original · survivor · unknown Completed exact-VIN sale reported at $46,000 on 2026-01-12. The marketplace classification supports survivor grouping; mileage is true-unknown and condition grade, A9 paperwork, drivetrain details, options, and originality evidence remain unknown.
1966 Buick Riviera GS chassis 494876H954963 Hemmings result
Auction sale $88,000

May 21, 2022 · Mecum Indy
Riviera GS chassis 494876H942603 with the 425/360-hp Super Wildcat V8 and automatic transmission · restored · unknown Completed vehicle-specific sale. Mecum explicitly describes a nut-and-bolt rotisserie frame-off restoration and 1,000 miles since restoration; CLASSIC.COM's exact result supplies the $88,000 amount and 2022-05-21 date. Condition grade, A9 paperwork, drivetrain originality, and restoration quality remain unknown.
1966 Buick Riviera GS chassis 494876H942603 1966 Buick Riviera GS chassis 494876H942603 Mecum result
Auction sale $16,500

Nov 14, 2021 · Bring a Trailer via CLASSIC.COM
73k-mile automatic GS classified as original or highly original · survivor · unknown Vehicle-specific result, not a generic value.
1966 Buick Riviera GS sold November 14, 2021
Auction sale $25,300

Jan 9, 2021 · Mecum Kissimmee
Riviera GS chassis 494876H941465 with a 425 V8 and automatic transmission · unknown · unknown Completed vehicle-specific sale. Mecum supplies the exact chassis, GS identity, 425, automatic, event, and sold status; Hagerty's exact past-sale record supplies the $25,300 result. Restoration state, mileage, A9 paperwork, induction details, and condition remain unknown rather than inferred from photographs.
1966 Buick Riviera GS chassis 494876H941465 1966 Buick Riviera GS chassis 494876H941465 past sale

Values move with paperwork, originality, options, condition, venue, and body style. High bids and guide values are labeled separately from completed sales.

Reference records

Options, Colors & Components

Source-backed details for trim, chassis, production, and authenticity.

Engine Details

**1966 Riviera 425 Nailhead engine bay with single four-barrel induction**Bruce Renfrew via Wikimedia Commons · CC BY-SA 3.0

MW 425 425 CID, single Quadrajet, 10.25:1 compression, 340 gross hp and 465 lb-ft · standard in base and Gran Sport Rivieras · engine assembly / specification
Dealer Super Wildcat conversion dual Carter four-barrels and related equipment, 360 gross hp · dealer-installed optional upgrade; not standard GS content · carburetor / specification

Transmission

Factory transmission Super Turbine 400 with variable-pitch torque converter

Options

MW 425 Wildcat reference for the 1966 Buick Riviera Gran SportClassic Muscle · Reference illustration

A9 Riviera Gran Sport High Performance Group optional · performance · High-performance springs and shocks, modified dual exhaust and Super Turbine transmission, 3.42 positive traction, 8.45 x 15 whitewall tires, chrome engine dress, and GS identification around the standard 340-hp 425. The reviewed registry transcription says C5 and C6 remained available with A9.
dealer-installed Super Wildcat dual-quad equipment dealer · performance · Raised the 425 rating to 360 hp; not standard GS content and requires separate documentation.
various Factory comfort, audio, and convenience choices optional · comfort · Seat, air-conditioning, power-equipment, radio, glass, steering, lighting, wheel, and trim choices were separate from A9; code-level applications and prices are listed below.
C5 15:1-ratio power steering optional · performance · Available only with A9; listed MSRP was $15.79.
D1 Sonomatic radio with manual antenna optional · comfort · Listed MSRP was $88.41.
D2 Sonomatic radio with electric antenna optional · comfort · Listed MSRP was $113.98.
D4 AM-FM stereo radio optional · comfort · Included front and rear speakers plus an electric antenna; listed MSRP was $266.81.
D5 AM-FM radio with electric antenna optional · comfort · Listed MSRP was $175.24.
D6 Rear-seat speaker optional · comfort · The registry table says it was included with D4 and lists a separate $16.84 price.
E2 Closed crankcase ventilation optional · safety · California-only equipment required with E6; listed MSRP was $5.27.
E6 Air Injection Reactor optional · safety · California-only equipment required with E2; listed MSRP was $44.73.
F1 8.45 x 15 whitewall tires optional · appearance · Available only with A9; listed MSRP was $42.41.
F8 8.45 x 15 red-line tires optional · appearance · Available only with A9 at no extra charge.
G1 Performance axle with positive traction optional · performance · Listed at $47.37 outside A9 and included at no extra charge with A9.
G4 Positive Traction differential optional · performance · Listed at $47.37 and described as included with G1 and A9.
G5 Economy axle optional · performance · No-extra-charge axle choice not available with A9.
H1 Trailer spring option optional · performance · Rear springs only; listed MSRP was $3.79.
I6 Air conditioner optional · comfort · Not available with I8; listed MSRP was $421.00.
I8 Less heater and defroster optional · comfort · The registry table lists this heater-and-defroster deletion at $95.90 and makes I6 unavailable with it.
K2 Cornering lights optional · safety · Listed MSRP was $33.68.
L1 Soft-Ray tinted glass optional · comfort · All-window application; listed MSRP was $42.10.
L2 Soft-Ray tinted windshield optional · comfort · Windshield-only application; listed MSRP was $28.42.
M7 Rear-window defroster optional · comfort · Listed MSRP was $21.05.
N2 Four-note horn optional · safety · Listed MSRP was $15.79.
O4 Two-door edge guards optional · appearance · Listed MSRP was $4.74.
O5 Remote-control outside mirror optional · comfort · Listed MSRP was $7.20.
P1 Carpet savers and handy mats optional · appearance · Listed MSRP was $12.19.
P2 Carpet savers optional · appearance · Listed MSRP was $6.77.
Q4 Six-way power bench seat optional · comfort · Bench-seat application; listed MSRP was $94.73.
Q5 Four-way tilt power seat adjuster optional · comfort · Available with bench or bucket seats; listed MSRP was $69.47.
R1 Power windows optional · comfort · Listed MSRP was $105.25.
S6 Electro-Cruise control optional · comfort · Listed MSRP was $63.15.
T1 Automatic trunk release optional · comfort · Listed MSRP was $12.63.
T2 Vacuum-operated door locks optional · comfort · Two-door application; listed MSRP was $44.73.
V2 Chrome-plated wheels optional · appearance · Listed MSRP was $89.47.
V4 Super Deluxe wheel covers optional · appearance · Listed MSRP was $57.89.
X1 Custom steering wheel optional · appearance · Listed MSRP was $52.63.
1A Reclining passenger seat and bench-seat headrests optional · comfort · Included driver and passenger headrests for bench seats; listed MSRP was $84.20.
1B Reclining passenger seat and bucket-seat headrests optional · comfort · Included driver and passenger headrests for bucket seats; listed MSRP was $84.20.
1C Regular-bench headrests optional · safety · Driver and passenger headrests for the regular bench seat; listed MSRP was $42.10.
1D Bucket or Strato-bench headrests optional · safety · Driver and passenger headrests for bucket or Strato-bench seats; listed MSRP was $52.63.
Custom trim - vinyl bench Vinyl Strato-bench custom trim optional · appearance · Listed MSRP was $168.40.
Custom trim - cloth bench Banbury cloth-and-vinyl Strato-bench custom trim optional · appearance · Listed MSRP was $168.40.
Custom trim - bucket Vinyl Strato-bucket custom trim optional · appearance · Listed MSRP was $168.40.
Special-order paint Single-car special-order paint optional · appearance · Applied to a color outside the standard chart; listed MSRP was $84.20.

Paint

**Blue 1966 Riviera Gran Sport, rear three-quarter view**Greg Gjerdingen via Wikimedia Commons · CC BY 2.0

A Regal Black factory · solid
B Riviera Gunmetal Poly factory · metallic
C Arctic White factory · solid
D Astro Blue Poly factory · metallic
E Midnight Blue Poly factory · metallic
F Blue Mist Poly factory · metallic
G Riviera Gold Poly factory · metallic
H Seafoam Green Poly factory · metallic
J Verde Green Poly factory · metallic
K Turquoise Mist Poly factory · metallic
L Shadow Turquoise Poly factory · metallic
M Riviera Red Poly factory · metallic
N Burgundy Mist Poly factory · metallic
R Flame Red factory · solid
S Riviera Champagne Poly factory · metallic
T Saddle Mist Poly factory · metallic
U Riviera Plum factory · solid
V Shell Beige factory · solid
W Silver Mist Poly factory · metallic
X Riviera White factory · solid
Y Cream factory · solid
Z Riviera Silver Green Poly factory · metallic

Appearance

Riviera GS fender scripts standard · badge
Riviera GS glovebox lettering standard · badge
All-new fastback body with hidden headlamps standard · other
Gran Sport wheel and tire presentation factory · wheel

Interior

Standard split bench seating standard · seat
Strato-bench or bucket-seat choices optional · seat
Driving console with automatic selector factory · console
Rotating-drum speedometer and full instruments standard · gauge

Chassis

Independent front suspension Suspension · standard
Control-arm live rear axle Suspension · standard
Gran Sport high-performance springs and shocks Suspension · standard
Power-assisted drum brakes Brakes · standard
Power front disc brakes Brakes · optional
Gran Sport positive-traction axle Rear axle · 3.42:1 · limited-slip · standard

Production

Super Turbine 400 reference for the 1966 Buick Riviera Gran SportClassic Muscle · Reference illustration

1966 Riviera, all configurations total · 45,348 · reported
1966 Riviera Gran Sport by option · 5,718 · reported
MZ Super Wildcat dual-quad 425 installed in Riviera Gran Sport by engine · 179 · reported

Authenticity

3.42 Positive Traction reference for the 1966 Buick Riviera Gran SportClassic Muscle · Reference illustration

Gran Sport identity Factory or dealer A9 evidence plus 3.42 positive traction, high-performance springs and shocks, chrome engine dress, and correct GS lettering · Window sticker, invoice, Protect-O-Plate, build records, axle, suspension, engine bay, trim, and body history · fraud detection
MW engine and induction MW stamp, partial VIN, castings, dates, single Quadrajet, chrome single-snorkel air cleaner, and finned covers agree · Engine pad, block, heads, carburetor, air cleaner, valve covers, and paperwork · numbers matching
Transmission and axle Super Turbine 400 and 3.42 positive-traction axle agree with component dates and records · Transmission, differential, ratio, axle evidence, and paperwork · date correctness
Paint, trim, and options Body plate codes and original evidence agree with finishes, seating, brakes, steering, and comfort equipment · Body plate, hidden paint, cabin, components, invoice, and window sticker · trim correctness

Still Researching

production The 45,348 total, 5,718 GS count, and 179 factory-assembled MZ Super Wildcat GS cars are reported consistently, but no primary Buick package ledger or broader configuration census was reviewed.
option packages A registry transcription now covers the published 1966 Riviera factory option-code, price, and dependency table, but the dated dealer order form, district revisions, omitted A9 price, and complete production-change record were not recovered.
interior Reviewed trim records establish major seating and material choices but not the full paint-by-trim matrix.
authenticity markers The model record cannot prove one car's original A9 order, drivetrain, axle, suspension, paint, trim, or options.