Extreme Exposure: 1975 Chevrolet Vega Cosworth #0192 – Sold?

May 9, 2022, Update – We just confirmed the listing for this “Classifind” expired, so with no replacement found we’re assuming this ride “Sold?” While this one got away, please reach out either by email or call us directly if you’d like to be informed when we come across something similar.

April 19, 2022 Update – The seller just lowered their asking price by an additional $1,000 for a revised asking price of $10,000. Two price reductions in a matter of one week confirm our suspicion the seller is very motivated to move this rare Vega.

April 16, 2022 Update – The seller just lowered their asking price by an additional $1,500 for a revised asking price of $11,000. We suspect the seller is very motivated to move this rare Vega.

April 1, 2022 Update – The private seller just replaced their expiring Craigslist ad with a fresh listing. In it, while the pictures and description remain the same, the seller elected to lower their asking price further to $12,500.

March 17, 2022 Update – The private seller of this rare Chevrolet Vega Cosworth just lowered their asking price by another one thousand dollars from $13,950 to $12,950.

March 4, 2022 Update – The private seller of this rare Chevrolet Vega Cosworth just lowered their asking price by one thousand dollars from $14,950 to $13,950.

You don’t get a second chance to make a great first impression. General Motors (“GM”) never learned that lesson. GM’s history is littered with cars plagued with quality problems at launch that lingered throughout the car’s life.  The 1970s GM poster child for bad quality was the Chevrolet Vega.  Five years into the launch of the Vega, the pricey but highly praised 1975 Chevrolet Vega Cosworth was not enough to shake the bad reputation. Vega Cosworth number 192 was originally listed in February 2022 on Craigslist in Aztec, New Mexico. The seller reports their car has only 52,500 original miles and features many new parts detailed in the Craigslist ad.

Currently offered for $10,000 (the original ask was $14,950), comparing that price against the Hagerty Insurance Online Valuation Tool confirms the private seller has their Cosworth Vega priced between this guide’s #4 “Fair” (Daily Driver) estimate of $9,200 and its #3 “Good” estimate of $16,000.  More conservatively, the  Collector Car Market Review Online Tool reveals the seller’s ask falls between this guide’s #2 “Very Good” estimate of $10,100 and its #1 “Excellent” appraisal of $16,000.

While Chevrolet produced the Vega subcompact from 1970, it did not launch a performance version of the car until 1975.  Chevrolet collaborated with British engineering firm Cosworth Engineering to develop an all-aluminum, 2.0 Liter, double overhead cam, inline-four engine. While the collaboration produced a total of 5,000 engines, Chevrolet built only 3,508 Vegas with the engine during the 1975 and 1976 model years.  More on that later.

Shortly following the launch of Vega in 1970, GM General Manager John DeLorean directed engine designer Calvin Wade to develop a high-performance version of the new all-aluminum 2.0-liter inline-four.  By the early 1970s, British firm Cosworth Engineering’s 3.0L DFV V8 dominated Formula One racing, so Wade partnered with the firm to develop a twin-cam cylinder head for Chevy’s two-liter inline-four.

By June, 1971 the collaboration produced a 170 horsepower prototype using dual Holley-Weber two-barrel carburetors. On Easter of 1972, GM President Edward Cole drove three Vegas for comparison: a base model, an all-aluminum small-block V8-powered prototype, and the Cosworth. He pledged approval from the Engineering Policy Group for DeLorean’s request to initiate Cosworth production. Approval of development aimed at U.S. Environmental Protection Agency (EPA) certification soon followed, and Wade began a 12-car development program to accumulate test mileage in a range of environments including high altitude, heat, and cold, to test the engine’s eligibility. At the GM desert proving ground, the car reached 122 mph.

In April, 1973 the design was frozen and two cars were built to accumulate mileage for EPA emission certification. However, engineers found the engine needed more time to develop new cam profiles to trade some high-end power for more low-end torque, and a tubular header to replace the cast iron exhaust manifold. Although delayed, the project now received higher priority, more engineering manpower and more funding. Chevrolet dealers began accepting large deposits for early delivery following press reports of what Chevrolet was working on.

The design was frozen again in January 1974. A stainless steel header was specified, to increase power between 2,000 rpm up and the 7,000 rpm redline. Camshaft lift and duration were eased back and the torque curve reshaped to a street-oriented peak of 5,200 rpm. Project coordinator William Large built two cars for durability testing. By April 1974, the engines ran “clean” for 40,000 miles, after which hydrocarbon curves on the first car rose far in excess of the permitted 3 grams per mile, owing to burned exhaust valves. For certification, five months’ durability miles would have to be reaccumulated.

Development resumed, to improve emissions durability and ready the engine for more stringent 1975 standards. The fuel injection was redesigned for better air distribution. High-energy electronic ignition and mandatory catalytic converter were added; also a Pulse Air system, functionally the same as an air pump but without the pump’s six-horsepower loss. A larger catalytic converter further guarded against power loss. More advanced ignition timing, and the lead-free fuel required with the converter, prevented exhaust-valve failure.

Chevrolet required all engines to survive 200 hours at full load. The Cosworth lasted over 500 hours. For a clutch burst test, Cale Wade revved the engine to 9,400 rpm under its own power without damage to clutch or engine. Three cars, in three different configurations, resumed mileage accumulation in September 1974 and after successful durability testing the Vega Cosworth was finally ready for sale for the 1975 model year.

All 2,061 1975 Cosworth Vegas came painted in black acrylic lacquer with gold “Cosworth Twin Cam” lettering on the front fenders and rear cove panel and gold pinstriping on the hood bulge, body sides, wheel openings, and rear cove. (Black was unavailable on other Vegas until mid-1976.) Most have black interiors. The custom interior with perforated vinyl seat trim (RPO ZJ1) was standard, with black cloth seat inserts a fifty-dollar option. About sixteen percent had white vinyl interiors. All Cosworths had a gold-colored engine-turned dash bezel, gold-plated dash plaque with build sequence number, 8,000 rpm tachometer, and Cosworth Twin-Cam Vega steering wheel emblem.

Vega Cosworths incorporated the ‘Torque arm’ rear suspension from the then-new Monza 2+2, and the axle, from the Monza 2+2, gives a 3.73:1 ratio from a 7.5-inch ring gear. A limited-slip differential was optional. Included were GT springs, shocks, and stabilizer bars (larger at the rear than the Vega GT’s); exclusive BR70-13 BSW radial tires on British-made 6 inch, gold-painted cast-aluminum wheels with Chevy center caps; black-finished wiper arms, and heavy-duty radiator. The Cosworth was the first Chevrolet passenger car with electronic fuel injection. Air conditioning, power steering, and power brakes were not offered.  A pilot line 1976 model was built in September 1975, and volume 1976 production began in December 1975.

Despite receiving great reviews from the motoring press, with a base price of $5,916, Vega Cosworths cost nearly double that of a $2,899 base Vega and were only $900 less than the $6,797 1975 Chevrolet Corvette. Consequently, Chevrolet only produced 3,508 Vega Cosworths before GM axed the brand at the end of the 1977 model year.

The AACA Museum, Inc. YouTube Channel provides this informative overview of the 1975 Chevrolet Cosworth Vega:

While the seller provides a number of detailed pictures, they serve as an example of why you shouldn’t photograph a car, especially a black one, during the middle of the day as it tends to look over-exposed.

Here’s the seller’s description:

“Beautiful 75 Cosworth vega
52,500 miles on the car
New rebuilt engine and transmission
Redone interior
New paint and graphics
New tires
New brakes
New window and door seals
New windshield
New alternator
New clutch
New cooling system
New u-joints
New muffler
Runs great, lots of fun
Show winner
Possible trade”

Do you have a 1975 Chevrolet Vega Cosworth story to share?  If so, comment below and let us know!