Chevrolet Corvette C3 454/365 Convertible
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Car producer : |
Chevrolet |
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Model: |
Corvette C3 454/365 Convertible |
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Year: |
1971 |
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Type: |
Roadster |
In 1970, fender flares were designed into the body contours to reduce wheel-thrown debris damage. New were egg-crate grills with matching front fender side vents and larger squared front directional lamps. The previously round dual exhaust outlets were made larger and rectangular in shape. Interiors were tweaked with redesigned seats and a new deluxe interior option combined wood-grain wood accents and higher-spec carpeting with leather seat surfaces. Positraction rear axle, tinted glass, and a wide-ratio 4-speed manual transmission were now standard. The 350 cu in (5.7 L) base engine (ZQ3) remained at 300hp (224 kW) and the L46 was again offered as a 350hp (261 kW) high performance upgrade. New was the LT-1, a 350 cu in (5.7 L) small-block V8 engine delivering a factory rated 370hp (276 kW). It was a solid lifter motor featuring a forged steel crankshaft, 4-bolt main block, 11:1 compression ratio, impact extruded pistons, high-lift camshaft, low-restriction exhaust, aluminum intake manifold, 4-barrel carburetor, and finned aluminum rocker covers. The new engine, making up less than 8% of production, could not be ordered with air conditioning but was fitted with a domed hood adorned with “LT-1” decals.
A special ZR1 package added racing suspension, brakes, stabilizer bars, and other high performance components to LT-1 cars. Big-block selection was down to one engine but displacement increased. The LS5 was a 454 cu in (7.4 L) motor generating 390hp (291 kW) SAE gross and accounted for a quarter of the cars. The LS7, which was advertised at 460hp (343 kW) SAE gross and had 454 cu in (7.4 L), was planned and appeared in Chevrolet literature but is not believed to have ever been delivered to retail customers, but offered as a crate engine. A short model year resulted in a disproportionately low production volume of 17,316, down nearly 60%. Rare options: ZR1 special engine package (25), shoulder belts in convertibles (475), LT-1 engine (1,287).
1971 cars were virtually identical in appearance to the previous model inside and out. This was the final year for the fiber optics light monitoring system, the headlight washer system, and the M22 heavy duty 4-speed manual gearbox. For the first time, air conditioning was installed on most of the cars, with nearly 53 percent so ordered. Engines were detuned with reduced compression ratios to tolerate lower octane fuel. The small blocks available were the 350 cu in (5.7 L) base engine, which dropped to 270hp (201 kW), and the high performance LT-1, now listed at 330hp (246 kW). The LS5 454 cu in (7.4 L) motor was carried over and produced 365hp (272 kW). Offered in ‘71 only was the LS6 454 cu in (7.4 L) big-block featuring aluminum heads and delivering 425hp (317 kW), highest of the 1970-72 series, and could be ordered with an automatic transmission. The ZR1 option was carried over for LT-1 equipped cars and the ZR2 option, offered this year only, provided a similar performance equipment package for LS6 cars, and restricted transmission to a 4-speed manual. Rare options: ZR1 special engine package (8), ZR2 special engine package (12), LS6 425-hp engine (188), shoulder belts in convertibles (677).
1972 was the last year for chrome bumpers at both front and rear, the vacuum actuated pop-up windshield wiper door, as well as the removable rear window common to all 1968-72 coupes. The key activated anti-theft alarm system became standard. The increasingly popular choice of an automatic transmission was installed in most corvettes for the first time, with nearly 54 percent so equipped. This year SAE net measurement for horsepower was now utilized (away from the previous SAE gross standard), and was largely responsible for the much lower engine output figures such as the 200hp (149 kW) rating on the standard 350 cu in (5.7 L) motor. This was the final year for the LT-1 engine, rated at 255hp (190 kW), and the ZR1 racing package built around it. Although the M22 HD 4-speed was no longer a Regular Production Option, it continued to be fitted to cars outfitted with the ZR1 package. The LT-1 could now be ordered with air conditioning, a combination not permitted the two previous years. The LS5 454 cu in (7.4 L) big block was again available and came in at 270hp (201 kW). Noteworthy is in ’72 the LS5 was not available to California buyers. This was the beginning of a trend where Chevrolet restricted certain power train choices to California buyers due to that state's practice of applying more stringent emission (smog) standards than mandated by federal regulations. Convertibles were a vanishing breed by ‘72, and the Stingray was no exception. It sold only 6,508 copies, amounting to 9% of the market, placing it number three; it was beaten by the number one-selling Cutlass Supreme, with 11,571, but beat the Impala's 6,456 and the Mustang's 6,401. Rare options: ZR1 special engine package (20), shoulder belts with convertibles (749), LT1 engine option (1,741).
