Friday, October 18, 2013

5k: American Little Mouse: 1975 Chevrolet Cosworth Vega

The word muscle derives from the Latin musculus which means literally "little mouse" - a reference to the way muscle looks when it moves under the skin.  The Chevrolet Vega was a mouse sized sub-compact built by GM from 1970-1977- initially touted as "Merica's answer to European sports cars.  Unfortunately a number of classic GM initial build quality defects tarnished the Vega's reputation and even sweet optional Cosworth DOHC 4-banger couldn't save the Vega from GM's compact model name cemetery.  Find this 1975 Chevrolet Cosworth Vega for sale in Palmdale, CA for $7,500 via craigslist.

The Cosworth Vega is arguably the best of the Vega breed, but that is dubious honor not unlike being the best hair in an armpit or the best sheet of toilet paper in a roll.  Regardless, all 1975 Cossy Vega's were finished in black acrylic lacquer with gold "Cosworth Twin Cam" script on the fenders and a total of 3500 cars were produced between 1975 and 1976.

The twin-cam engine was a technological feat for 1975 and while power was down considerably from the initial prototypes (partially from the change from SAE gross to net power ratings, but also because of smog requirements) the final production version put out 110 horsepower and 108 ft-lbs of torque.  The all-alloy engine was the first passenger car from GM to feature electronic fuel injection and featured forged piston and crankshaft instead of the typical cast pieces.   All of this technology came with a price and the Cosworth Vega cost almost as much as a base Corvette in 1975.

The inside of this Vega shows a black interior in good shape and the desirable 4 5-speed (ed note: update per comments from Larry, this is a 4-spd car, the 5 speed was introduced in 1976)  manual transmission.  The Cosworth Vega came with a special 8,000 rpm tach, even though the engine only revv'd to 6500 rpm. 

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  1. Twin-cam engines in 1975 were a technological feat for General Motors. As far as the rest of the world is concerned, twin-cam engines were a technological feat in the 1910's and 1920's.

    I dig the lines on this car, and the rarity is also a draw. I hope this goes to someone who appreciates it... by driving the wheels off of it. I'd like to see this one at Early Rodders.

  2. Ad says 4-speed, not 5. It looks good, but I'd still question the 22K mile claim. While I'm well aware of the Vega's reputation, I've always liked the look - particularly the Cosworth version. A friend's older brother bought one new. Not very reliable or well made, but not that much worse than the other crap GM was peddling at the time. Performed pretty well too (again, for the time).

    1. Noted and corrected! I'm a forward thinker..?

  3. I've always wondered what these Cosworth engines might be capable of if somebody unsmogged, ported, polished, unchoked, unclogged, de-airpumped, and basically undid all of the evil things the factory did to them during the mid-seventies.

  4. From wikipedia "Known at Cosworth Engineering as Project EA, a Cosworth racing engine based on the Vega aluminum block produced a reported 260 hp (190 kW) and powered Chevron and Lola race cars to wins in the 2-liter class in their first outings. The ZO9 Cosworth Vega engine is a de-tuned version. Bore, stroke and valve sizes are identical but it lacks the EA engine’s dry sump lubricating system (unnecessary in a road car), has a lower compression ratio and different valve timing, and uses Bendix electronic fuel injection instead of Lucas mechanical injection to cope with a wider range of operating conditions as well as emission controls.[2]"
    and then the production version:
    "In June, 1971 the prototype gave 170 hp (130 kW) on dual Holley-Weber two-barrel carburetors. "
    I'd guess that an uncorked version of the factory engine (new intake, low restriction exhaust, higher compression, ported head, MSD style ignition, no smog bs) would be good for at least 200 hp at 7000 rpm.

  5. I was looking for a new car in 1974 when i .bought a 74 Vega Gt not my first choice but that is life. The vega motors sucked oil so i found a 75 Buick 231 V6 with 600 miles on it out of a wrecked Skyhawk. was pretty easy swap and had great power and mpg. The cosworth motors were no better as far as oil consumption. These car also came in white and red i believe (cosworth vega) Don't think these cars worth 7.5k maybe to a collecter but plenty of kooler cars out there for the money that are reliable and more fun to drive.

  6. The Early Vegas 71-72 had borrowed the Opel 4 speed that were to light so i believe in 73 they went to the Saginaw 4 speed which was a much heavier duty unit. The 5 speed offered later on was also on the fragile side.


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