Steve Magnante's 1001 Corvette Facts. Steve Magnante

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СКАЧАТЬ The Corvette’s ladder-type steel frame featured fully boxed side rails not just in the middle region under the cockpit, like Chevrolet convertible passenger cars, but all the way to the horns on each end. The total weight was 213 pounds. For comparison, the fully assembled Corvette bare body weighed 340 pounds.

      86 To cut costs, the Corvette’s front suspension shared many passenger-car components. Again, it was ex–Rolls-Royce chassis guru Maurice Olley who oversaw adapting the Bel Air parts for use on the new sports car. Notable changes included specific steering linkage and revised front anti-sway bar positioning. Like all pre-1955 Chevrolet passenger cars, the Corvette employed kingpins instead of ball joints, a detail that hampered ideal handling until 1963 with the arrival of the Sting Ray.

      87 Power steering wasn’t offered on any Corvette until 1963, but to give the Corvette better reflexes in 1953, the Saginaw manual steering box was given a faster 16:1 ratio. The passenger-car steering ratio of the day was 19.4:1.

      88 The passenger-car parts bin also contributed major brake components to the Corvette program. The same 11 × 2.00/11 × 1.75-inch drums (front/rear) remained, but the piston in the brake master cylinder was 1/8-inch larger for quicker application. The brake proportioning valve was adjusted to deliver 3 percent less forward bias. This switch from the passenger car’s typical 56/44 (front/rear) to 53/47-percent proportion ratio was needed to complement the Corvette’s more even front/rear weight distribution.

      89 Chevrolet correctly predicted that “Midnight Auto Supply” crews would be highly attracted to the exciting new Corvette. To ease law enforcement’s efforts to identify purloined Corvettes, a hidden VIN stamping was applied to the top of the 1953 frame in addition to the stainless-steel VIN tag affixed to the driver-side door-hinge pillar. Visible through the driver-side rear wheel opening, the entire 10-character identification sequence was stamped atop the main frame rail where it transitioned upward over the axle. For 1954 and up, the hidden VIN was moved atop the central X-member near the driver’s seat and is almost impossible to read with the body in place.

      90 Long before the advent of cast- and forged-aluminum wheels, Corvette shared its unadorned 15 × 5-inch Kelsey Hayes steel rims with standard Chevrolets. The only detail setting them apart was color. All 1953 and 1954 rims were painted Sportsman Red to complement the interior. For 1955, Chevrolet shuffled the deck to suit the growing body color palette. Cars painted Gypsy Red (a different shade than Sportsman Red), Harvest Gold, and Corvette Copper received color-keyed rims. 1955 cars painted Polo White or Pennant Blue reverted to Sportsman Red wheels.

      91 The front side of Corvette’s steel wheels wore pretty shades of paint, but what about the reverse side? In a seemingly random fashion, some rims were painted to match the outboard face, and others were merely sprayed with a hasty coat of semi gloss black to prevent surface rust.

      92 A production hiccup forced the use of simple, bulbous 1953 Bel Air wheel covers on the first 25 Corvettes built in 1953. Or did it? Although there exist many GM photos of Bel Air–capped 1953 Corvettes, research indicates few, if any, reached showrooms with them. General Motors likely replaced them with the correct spinner-type covers before retail shipment.

      93 Although the bodies they carried differed dramatically, the frames underneath the Corvettes were almost the same from 1953 to 1962. The 11 body-mount locations, suspension geometry, and general characteristics remained unchanged. The most note-worthy change came in 1955 when the passenger-side frame horn received a stamped notch to clear the V-8’s protruding mechanical fuel pump.

      94 You had to stop and look for it, but the Corvette’s 58.8-inch rear track width was almost 2 inches wider than the 57.0-inch front measurement. This seeming mismatch is actually common throughout the automotive world and exists to allow front-tire-to-body clearance at full steering lock. Remember, the rear axle doesn’t steer.

      95 Although Corvette suspensions were historically more advanced than those installed on Chevrolet passenger-car models, in 1955 Chevrolet elected to retain the compromised kingpin-style front suspension rather than upgrade to the more advanced ball-joint front suspension fitted to the all-new 1955-on passenger cars. It was one of the few times Corvette technology lagged behind.

      96 The kingpin/ball-joint controversy centers on the union between the A-arms and front-wheel spindles. Ball joints have swiveling studs with far greater range of motion than kingpins. This was at the core of Corvette’s compromised front-suspension geometry through the 1962 model run. It is noteworthy that General Motors declined to invest in a ball-joint upgrade for Corvette despite the fact that 1955-on passenger-car parts could have easily been adapted.

      97 In keeping with the general theme of “lower, wider, longer” that prevailed in 1950s Detroit, the Corvette’s 57-inch front and 58.8-inch rear track widths were 6 and 9 inches wider, respectively, than the front and rear track widths of the Jaguar XK120, one of the British sports cars General Motors “benchmarked” to help guide Corvette development.

      98 The Corvette’s worm-and-sector steering box may have been given a quicker ratio than its passenger-car forebears, but drivers knew to keep rolling slowly when parking. Optional power assist didn’t arrive until 1963.

      99 Despite the jump from 155 to 195 hp that came with the V-8 in 1955, Corvettes continued to use the same four-leaf rear leaf springs fitted since 1953. And unlike certain subsequent V-8 models that came with traction bars, the 1955 rear suspension wasn’t bolstered to ward off axle hop.

      100 With the vast majority of 1955 V-8 Corvettes equipped with Powerglide automatic transmissions (about 630 of 700), the need to curb axle hop wasn’t urgent. That’s because the Powerglide’s torque converter cushioned the delivery of power to the axle more effectively than a clutch-equipped manual transmission. The abrupt jolts generated by a vigorously operated manual transmission could upset the tire/road contact patch and lead to axle tramp. Because only a small population of 1955 Corvettes had manual transmissions, the one-size-fits-all rear suspension/axle strategy enjoyed a final year in 1955.

NUMBER CRUNCHING AND PRESS COMMENTARY

      101 Legendary magazine road tester Tom McCahill tested a 1954 model in the May 1954 issue of Mechanix Illustrated and squashed the myth that 6-cylinder Corvettes were slowpokes in their day. He said the 1954 Corvette could “whip up to 60 mph in 11.2 seconds, which is fast enough to embarrass a 1954 Cadillac by several lengths.”

      102 Every mass-produced automobile model on the face of the planet was first built in small quantities as assembly line workers learned assembly details in slow motion. Typically, the first few dozen to 100 units of any new model fall into this “pilot car” category. However, in the case of the 1953 Corvette, because General Motors was working with an unfamiliar medium, fiberglass, the process was magnified. Every one of the 300 Corvette roadsters built in 1953 at the Van Slyke Avenue plant in Flint, Michigan, was hand assembled, and it can be said that no two were strictly identical. By contrast, the 1954 Corvette assembly plant in St. Louis benefitted from the many lessons gleaned during the six-month-long pilot run. The same 300 cars that took almost six months to assemble in Flint could be completed in St. Louis in 10 days!

      103 In an early 1955 issue of Motor Life, writer Ken Fermoyl wrote of the new 265 V-8 1955 Corvette, “The engine fits so nicely, in fact, that one suspects that the possibility of using a V-8 was considered when the Corvette was designed.” Was a V-8 even available in late 1952 when the Corvette concept was taking shape? Yes. When Ed Cole became chief engineer at Chevrolet in 1952, he scuttled a nearly finalized V-8 design, complete with running prototypes. Details are scarce, but the 231-ci V-8 likely had СКАЧАТЬ