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Full-size performance

1966 Pontiac Catalina 2+2 421

Full-size performance powered by 1966 Pontiac 421 V8.

White 1966 2+2 hardtop front three-quarter view
Series 254 2+2
Bodies 25437 hardtop; 25467 convertible
Standard engine 421 four-barrel, 338 gross hp
Top engine 421 HO Tri-Power, 376 gross hp
Production 6,383 total

Story

For 1966, Pontiac made the 2+2 its own full-size Series 254 rather than carrying it as an option on a Catalina. The two bodies were the 25437 pillarless hardtop and 25467 convertible. Both combined Pontiac's long-wheelbase full-size chassis with a standard 421 four-barrel, dual exhaust, floor-shifted three-speed, bucket-seat cabin, and model-specific exterior trim.

The standard 421 produced 338 gross horsepower and 459 lb-ft. Buyers could order the 356-hp Tri-Power version or the 376-hp 421 HO, which paired three Rochester two-barrels with its own camshaft, valve springs, exhaust and cooling equipment. All three are configurations of the same 1966 2+2 model and belong on this page rather than separate near-duplicate pages.

The standard manual was a fully synchronized three-speed with a Hurst floor shifter and 3.42 axle. Wide- and close-ratio four-speeds and Turbo Hydra-Matic were optional; the automatic's standard axle was 3.23, while air conditioning could change the specified ratio. Safe-T-Track was extra. The 121-inch-wheelbase chassis used independent front control arms, a four-link coil-spring live rear axle, and 11-inch self-adjusting drums. Pontiac's aluminum eight-lug hub-and-drum equipment remained optional.

The 2+2's visual identifiers included 421 and 2+2 emblems, vertical slots behind the doors, pinstriping, full wheel discs, and the 1966 twin-lens taillamp treatment. Inside were Strato bucket seats, full carpeting, special door trim, and all-Morrokide upholstery offered in four brochure color families. A console, gauges, tachometer, clock, and vacuum gauge were order-dependent equipment rather than universal identifiers.

Pontiac built 6,383 2+2s for 1966: 2,208 with synchromesh transmissions and 4,175 with Hydra-Matic. The reviewed records do not provide a reliable hardtop-versus-convertible or engine-configuration split. Authentication starts with a 25437 or 25467 identity and the individual PHS invoice or billing history, then checks the engine, induction, transmission, axle, paint, trim, and component dates. Badges, vertical slots, buckets, or a 421 help inspect a car, but none substitutes for its records.

White 1966 2+2 hardtop approaching at a showGreg Gjerdingen via Wikimedia Commons · CC BY 2.0

Price history

Values

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

Original Price

A verified base MSRP is not yet available. Documented option and charge prices are shown below.

Market Observations

  • Price guide value $46,000

    Jul 31, 2026 · Hagerty Valuation Tools · Current guide point

    July 2026 condition #3 guide for the 1966 Catalina 2+2 convertible with the 421cid/338hp four-barrel V8 · unknown · good Exact model, body, and standard-engine guide benchmark before the displayed factory-air-conditioning and Ventura-package adjustments. Transmission, axle, options, documentation, originality, and individual-car condition require separate normalization; no adjustment is calculated into this amount.
  • Auction sale $35,000

    Feb 21, 2026 · Bring a Trailer

    25467 convertible chassis 254676C102816 with the represented 421 four-barrel and Turbo Hydra-Matic · restored · unknown Completed sale at the venue-published winning bid before buyer fees. The 2018 refurbishment included repaint, reupholstery, engine and transmission rebuilds, a replacement top, aluminum radiator, aftermarket stereo, and other service; total mileage, component originality, documentation depth, and locked condition grade remain unknown.
  • High bid $41,500

    Oct 4, 2023 · Hagerty Marketplace

    25467 convertible chassis 254676C109825 represented with the 421/338-hp four-barrel V8 and Turbo Hydra-Matic · restored · unknown Auction ended at the stated high bid rather than a completed sale. The restored car has reupholstery, an aftermarket stereo and gauges, TMU mileage, and seller-supplied configuration and condition claims; no locked condition grade or numbers-matching conclusion is inferred.
  • Auction sale $19,800

    Mar 14, 2019 · Mecum Auctions

    25467 convertible chassis 254676C112261 represented with an automatic transmission and 421 badging · restored · unknown Completed sale of a recently restored Series 254 convertible. The body VIN establishes 2+2 identity and the model's standard 421 configuration, but the sparse archive does not identify the installed engine, carburetion, transmission unit, paperwork, mileage, or restoration quality; 421 badging alone is not component-authentication evidence.

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

  • 421 four-barrel 338 gross hp at 4,600 rpm; 459 lb-ft at 2,800 rpm; 10.5:1 compression · standard 1966 2+2 · engine assembly / specification
  • Standard Carter AFB 4033S with synchromesh; 4037S with Turbo Hydra-Matic · 421 four-barrel · carburetor / specification
  • 421 Tri-Power 356 gross hp at 4,800 rpm; 459 lb-ft at 3,200 rpm; 10.75:1 compression · optional 1966 2+2 · engine assembly / specification
  • Rochester Tri-Power carburetors manual 7025078 front, 7026075 center, 7025079 rear; automatic 7024078 front, 7026074 center, 7024079 rear · 356-hp and 376-hp Tri-Power · carburetor / specification
  • 421 HO Tri-Power 376 gross hp at 5,000 rpm; 461 lb-ft at 3,600 rpm; 10.75:1 compression · optional 1966 2+2 · engine assembly / specification
  • 421 HO valve timing 288-degree intake, 302-degree exhaust, 63-degree overlap, 0.409-inch lift · 421 HO only · camshaft / specification
  • Bore and stroke 4.09375 x 4.00 inches · all 421 configurations · engine assembly / specification

Transmission

  • Factory transmission Standard all-synchromesh three-speed: 2.42, 1.61, 1.00; reverse 2.33
  • Factory transmission Wide-ratio four-speed: 2.52, 1.88, 1.46, 1.00; reverse 2.59
  • Factory transmission Close-ratio four-speed: 2.20, 1.64, 1.28, 1.00; reverse 2.27
  • Factory transmission Turbo Hydra-Matic 400: 2.48, 1.48, 1.00; reverse 2.08

Options

Three 421 Configurations for the 1966 Pontiac 2+2Classic Muscle · Reference illustration

Paint

1966 2+2 rear emblem and twin-lens taillamp detailGreg Gjerdingen via Wikimedia Commons · CC BY 2.0

Interior

Chassis

Production

Three Transmission Paths for the 1966 Pontiac 2+2Classic Muscle · Reference illustration

Authenticity

Axle Pairings for the 1966 Pontiac 2+2Classic Muscle · Reference illustration
  • Series and body identity 1966 Series 254 body style 25437 hardtop or 25467 convertible · VIN, cowl/data plate, title, body structure, and individual documentation · fraud detection
  • Factory documentation Individual factory invoice or billing history identifies the Series 254 2+2 and its ordered equipment · PHS documentation issued for the VIN, surviving billing history, or original paperwork · fraud detection
  • 421 engine configuration Factory 421 four-barrel, Tri-Power, or HO configuration matching the individual invoice and period specifications · PHS documents, engine unit code and date, block and head dates, induction, cam, and exhaust equipment · numbers matching
  • Transmission and axle pairing 3.42 standard manual or 3.23 standard automatic, adjusted where documented for air conditioning or close-ratio four-speed · PHS invoice, transmission identifiers and dates, axle code and ratio, and air-conditioning equipment · date correctness
  • 2+2 exterior treatment 421 and 2+2 identification, vertical rear-quarter slots, pinstriping, twin-lens taillamps, and correct wheel treatment · Original attachment evidence, hidden paint, trim details, factory photographs, and restoration records · trim correctness
  • Paint and interior Factory paint and trim codes correspond to a documented 1966 2+2 combination · Cowl/data plate, hidden original finishes, upholstery evidence, invoice, and restoration documentation · trim correctness

Still Researching

  • production Reviewed production records provide the total and transmission split but no reliable 25437-versus-25467 body split or engine-configuration split.
  • authenticity markers Model-level sources cannot authenticate an individual car, and the reviewed primary documents do not provide a complete engine-unit, transmission, and axle code table for every combination.

Codes & names

Names & Engine Codes

Common names and codes are grouped so LS6 references point to the same engine, not separate pages.

Full-Size Performance Chassis for the 1966 Pontiac 2+2Classic Muscle · Reference illustration
1966 Pontiac 421 1966 Pontiac 421 V8
1966 2+2 421 four-barrel 1966 Pontiac 421 V8
1966 421 Tri-Power 1966 Pontiac 421 V8
1966 421 HO 1966 Pontiac 421 V8

Photo and video gallery

Gallery

5 photos and videos

Sources & Documentation

Reader contributions

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