Monday, April 29, 2013

Chevrolet Cosworth Vega vs. Mercury Capri II

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The mid-1970s were like the Middle Ages for car enthusiasts, a dark era marred by an oil embargo and increasing concern about smog that had automakers struggling to meet new emissions and fuel-economy standards. As horsepower and compression ratios plunged, new safety regs and 5-mph bumper standards sent curb weights on an upward spiral and blighted styling with chromed railroad ties hanging off both ends of most cars. As the industry and buyers started to think smaller -- much as they are now -- compact coupes with a modicum of style were viewed as potential new-age sports cars. When the 1964.5 Mustang sold out its expected annual volume in three months, Ford of Europe went to work on a Mustang of its own, assigning the design to Iowa native Phil Clark, who also penned the Mustang's galloping horse logo. He gave the vehicle long-hood/short-deck proportions and based it on stodgy compact-car underpinnings (Europe's smaller Cortina instead of our Falcon) -- it was even code named Colt during development, to drive home its ponycar mission. The Ford Capri went on sale in Europe in early 1969 with seven engine choices, and proved popular enough (185,000 sold in its first year) to warrant bringing a 1.6-liter version to North American Lincoln-Mercury dealers in 1970. At the time, it was almost 20 inches shorter and 9 inches narrower than the Mustang -- not to mention lighter and more agile. 1976 Chevrolet Cosworth Vega Mercury Capri II Side In Motion The lithe Capri was well-positioned for the mid-'70s push toward downsizing that demoted the Mustang II to the Pinto's platform in 1974. The two cars were then priced and equipped about the same, but the still smaller and lighter Capri outperformed its Yank counterpart when comparing either of its shared engines (the 2.3-liter four or 2.8-liter V-6). The refreshed Capri II that arrived for 1976 with crisper, cleaner styling actually grew by an inch in length (mostly for bumper standards) and 2 inches in width (to increase rear track for better handling), and gained about 150 pounds. Much of the weight was expended reinforcing the rear end to accommodate a new hatchback that greatly increased the Capri's utility value -- trunk space bloomed from 8.1 cubic feet to 22.6 with rear seatbacks folded. Larger rear windows improved visibility; a fourth leaf in the rear springs allowed the others to be softened for improved ride; a new three-speed automatic transmission was introduced; and power steering (using a Jaguar pump) joined the options list, along with a tilt-or-slide sunroof.
  • 1976 Mercury Capri II Front Three Quarter In Motion
  • 1976 Mercury Capri II Front Three Quarters In Motion
  • 1976 Mercury Capri II Side In Motion
  • 1976 Mercury Capri II Taillight
  • 1976 Mercury Capri II Unleaded Gasoline Only
  • 1976 Mercury Capri II Wheels
Rated at 109 hp and 146 lb-ft of torque and packaged with dual exhaust, bigger brakes, and heavy-duty springs and shocks, not to mention unique gear ratios, the 2.8-liter Cologne-built pushrod V-6 engine gave what passed for sporting performance in 1975-'76. Its 17.4-second, 79.4-mph quarter mile bested its class in a June 1975 comparison by 1.9 seconds -- of course, that time the "class" consisted of an AMC Pacer I-6 plus a Mercury Bobcat and (Vega-twin) Pontiac Astre with I-4s. The much more fitting comparison test that inspired this matchup was Motor Trend's October 1975 "Black Gold" hot hatch face-off between a Capri II S 2.8 and Chevrolet's similarly powerful but considerably pricier Cosworth Vega. That car's gestation story is considerably more involved. 1976 Mercury Capri II Front End 2 In late 1969, with the highly anticipated and much-ballyhooed Vega nearing production, Chevy boss John DeLorean suggested that Jim Musser -- Vega project leader and former Can-Am racing program honcho -- contact the racing-engine experts at Cosworth to see if they'd be interested in transforming Chevy's new aluminum block into a 300-hp racing engine. Co-founder Keith Duckworth was concerned about the die-cast block's siamesed, free-standing "open-deck" cylinder bores, but agreed to investigate further. Chevrolet allocated some Vega sales and marketing budget to fund the racing engine's development, and DeLorean suggested the plans include a twin-cam Cosworth performance version for the street. To get from the stock 2.3 liters down to just under 2.0 liters for European formula racing, the stroke was reduced from 92.1 to 80.3 mm. Duckworth's instincts proved correct: The bores were expanding and fretting their head gaskets. The gasket and block were tweaked, and by September 1971, the engine, dubbed EAA, was reliably developing 270 hp at 9000 rpm on the dyno. Installed in a Chevron B19 chassis, it proved devilishly quick but unreliable, suffering cracked blocks, blown gaskets, and oiling problems. Cosworth ceased development in fall 1972.
  • 1976 Mercury Capri II Cockpit In Motion
  • 1976 Mercury Capri II Engine
  • 1976 Mercury Capri II Interior
  • 1976 Mercury Capri II Interior Rear Seats
  • 1976 Mercury Capri II Exhaust Tip
  • 1976 Mercury Capri II Front End
Plans for the detuned street version forged on, however, with lower compression and different cams; conventional instead of dry-sump lubrication, but a similar forged and magnafluxed steel crank; forged aluminum pistons; and the same bore, stroke, and valve sizes. In place of the Lucas mechanical injection, Chevy turned to Bendix for electronic injection to gain valuable field experience on the limited-edition Cosworth Vega prior to wider rollout of this technology to meet forthcoming regulations. By mid-'72 this technological gem was spinning out 170 hp at 7600 rpm and 126 lb-ft at 4000 -- heady stuff in a 2300-pound car -- but part-throttle driveability was poor and emissions weren't clean enough. By May 1973, output was down to 130 hp and 116 lb-ft, but Car and Driver took a prototype to 60 mph in 7.7 seconds with a 16.2-second 85-mph quarter mile, proclaiming, "The only four-passenger coupes faster than a Cosworth Vega have a Detroit V-8 under the hood." As production got pushed back to 1975, emissions regs prompted more detuning, cam reprofiling, and the addition of a catalytic converter. With less camshaft overlap than in the stock Vega and an innovative pulse-air injection system that did without a power-robbing air pump, the engine finally passed emissions -- and with such flying colors that it ranked as the cleanest car ever tested by the EPA's Ann Arbor, Michigan, lab. It was also GM's first car to test legal in all 50 states with one state of tune, but output of Cosworth's EAA engine, dubbed LY3 or RPO Z09, had shrunk to 110 hp at 5600 rpm and 107 lb-ft at 4800 -- only 23 hp more than the GT, with 6 fewer lb-ft and now with heavier 5-mph bumpers to lug around.

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