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Compact performance

1975 Chevrolet Cosworth Vega

Compact performance powered by 1975 Cosworth Twin Cam 122.

Black-and-gold 1975 Cosworth Vega, front three-quarter view
Engine 122-cu-in DOHC four, 110 hp
Transmission M20 Saginaw four-speed
Rear axle 3.73; Positraction optional
Wheelbase 97 inches
1975 production 2,061

Story

The 1975 Cosworth Vega was Chevrolet's small, technically ambitious performance car: a numbered black-and-gold hatchback with a 2.0-liter twin-cam engine, electronic fuel injection, a four-speed manual, and a handling package built around a Monza-derived torque-arm rear suspension.

The engine is more than a dressed-up Vega four. Chevrolet de-stroked the aluminum block to 122 cubic inches and paired it with a Cosworth-designed aluminum head, dual overhead camshafts, four valves per cylinder, forged pistons, Bendix pulse-time fuel injection, high-energy ignition, and a stainless tubular header. Factory specifications list 110 horsepower and 107 lb-ft.

Every 1975 model used an M20 Saginaw four-speed and a 3.73 axle; G81 Positraction was optional. Unique springs, shocks, stabilizer bars, a torque arm, and a forward-mounted Panhard bar made the chassis as important as the engine. Manual front discs and rear drums supplied braking.

All 2,061 first-year cars were painted black with gold graphics and Cosworth lettering. The gold dash plaque is useful history, but the VIN's E engine code, body tag, engine and component numbers, dates, original paperwork, black paint, interior, and surviving package hardware must agree before an individual car is described as authentic.

Cosworth Vega preserved at the GM Heritage Center, retained as an exact-model front exterior referenceTino Rossini via Wikimedia Commons · CC BY 2.0

Price history

Values

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

Market Observations

  • Auction sale $6,800

    Feb 25, 2026 · Cars & Bids

    Cosworth Vega no. 1,503, chassis 1V77E5U258406, with 2.0L engine, four-speed, and 73,100 miles displayed · survivor · unknown Completed winning bid before buyer fees. The long-owned car had an aluminum radiator, reported recent belt service without supporting invoices, and disclosed chips, scratches, and rust at the sills, doors, and underbody. EFI retention, mileage, broader component originality, rust extent, and a locked condition grade are not independently established.
  • Auction sale $5,351

    Jan 20, 2026 · Bring a Trailer

    Running black-over-black four-speed survivor project with retained EFI, serialized plaque, corrosion, worn paint, and disclosed underside issues · survivor · project Vehicle-specific completed result, not a generic model value.
  • Auction sale $28,600

    Jan 14, 2023 · Mecum Kissimmee

    Cosworth Vega no. 1,435, chassis 1V77E5U258223, with 2.0L twin-cam engine, four-speed, and 2,295 miles displayed · survivor · unknown Venue-published completed result; hammer-versus-fee basis is not disclosed. The listing reports indoor storage and includes the original window sticker, EPA sticker, and CVOA membership, but it does not independently lock EFI originality, mileage, component originality, or a condition grade.
  • High bid $9,400

    Sep 30, 2020 · Bring a Trailer

    Cosworth Vega no. 1,289, chassis 1V77E5U250861, with four-speed, dual Weber conversion, and removed factory EFI included · modified · unknown Reserve-not-met high bid, not a completed sale. The car had been repainted, received door pinch-weld and battery-tray repairs, and retained the twin-cam engine while using carburetors in place of the factory injection. The displayed 33k miles, drivetrain originality, rust extent, and a locked condition grade are not independently established.

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

Cosworth Twin Cam engine and Bendix EFITino Rossini via Wikimedia Commons · CC BY 2.0
  • Cosworth Twin Cam 122 3.50 x 3.16 inches, 8.5:1 compression, 110 hp and 107 lb-ft · standard and exclusive to the 1975 Cosworth Vega · engine assembly / specification
  • Cosworth aluminum cylinder head dual overhead camshafts and four valves per cylinder · belt-driven cam carrier on the de-stroked Vega aluminum block · cylinder head / specification
  • 1975 VIN engine code E · fifth VIN position on an individual 1975 Cosworth Vega · other / assembly code

Transmission

  • Factory transmission M20 Saginaw four-speed manual

Options

Cosworth Twin Cam 122 reference for the 1975 Chevrolet Cosworth VegaClassic Muscle · Reference illustration
  • Z09 Cosworth Vega package factory · performance · Combined the twin-cam EFI engine, M20 four-speed, 3.73 axle, unique suspension, wheels, instruments, black paint, and gold identification.
  • G81 Positraction optional · performance · Limited-slip carrier with the standard 3.73 ratio.
  • ZJ1 Custom interior standard · interior · Perforated vinyl seating was standard; black cloth inserts were extra cost.
  • U14 Special instrumentation standard · interior · Gold engine-turned panel with 120-mph speedometer, 8,000-rpm tachometer, clock, and auxiliary gauges.

Paint

1975 Cosworth Vega, rear three-quarter viewMercurySable99 via Wikimedia Commons · CC BY-SA 4.0

Production

Chevrolet Cosworth Vega period press photographChevrolet via Wikimedia Commons · Public domain
Bendix Electronic Injection reference for the 1975 Chevrolet Cosworth VegaClassic Muscle · Reference illustration

Authenticity

Four-Speed Only reference for the 1975 Chevrolet Cosworth VegaClassic Muscle · Reference illustration
  • Model identity 1V77E5 VIN, 1HV77 body, Z09 paperwork, and serialized dash plaque agree · VIN, body tag, window sticker, invoice, build sheet, dashboard, and registry history · fraud detection
  • Engine identity VIN-code E engine, component numbers, production/date code, vehicle VIN stamp, EFI, twin-cam head, and header agree · VIN, block, bellhousing flange, head, cam carrier, EFI hardware, exhaust, and records · numbers matching
  • Transmission and axle M20 four-speed ratios and 3.73 axle evidence agree; G81 requires separate proof · Transmission stamp, shifter and tunnel, axle code, ratio, dates, and paperwork · date correctness
  • Paint, trim, and cabin Code 19 black paint, gold graphics, 1975 body details, trim code, numbered plaque, wheels, and hidden finishes agree · Body tag, hidden paint, graphics, wheels, cabin, plaque, fasteners, and period photos · trim correctness

Still Researching

  • production The 2,061 count is consistent in registry and model references, but no Chevrolet package-production ledger was reviewed.
  • interior Trim 19Y is documented on a 1975 Cosworth Vega, but the complete Z09 matrix remains unresolved. Chevrolet's service supplement says exterior paint and interior trim were black-only and mentions a choice of seat fabrics; the registry reports white vinyl on about 16 percent of 1975 cars. The final-issue service-parts catalog lists 02Y, 11Y, 19D, 19E, 19W, and 19Y for the broader 1HV77 hatchback body but does not identify which combinations were Z09-eligible or their effective dates.
  • authenticity markers The model record cannot establish one car's original engine, EFI, transmission, axle, paint, trim, plaque, or ownership history.

Codes & names

Names & Engine Codes

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

3.73 Rear Axle reference for the 1975 Chevrolet Cosworth VegaClassic Muscle · Reference illustration
1975 Cosworth Twin Cam 1975 Cosworth Twin Cam 122
1975 Z09 engine 1975 Cosworth Twin Cam 122
1975 VIN-code E engine 1975 Cosworth Twin Cam 122

Photo and video gallery

Gallery

5 photos and videos

Sources & Documentation

Reader contributions

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