Steve Magnante's 1001 Corvette Facts. Steve Magnante

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СКАЧАТЬ photograph it, but trust me, it’s there (I felt it with my hands). Directly behind the instrument cluster is a horizontal structural brace supporting the steering column and dash assembly. Directly behind the parking lamp lens, and precisely where a 3-speed column-shift actuator rod would pass, this brace is formed with a hump that serves no purpose except to allow passage of a shift actuator rod. These clues suggest Chevrolet considered offering a column-shifted 3-speed manual transmission, but held off. Was there concern that the balky three-on-the-tree would be as unpopular as the Powerglide automatic?

      53 The eventual shifter used to manipulate the two-speed Power-glide was a floor-mounted lever set conveniently next to the driver’s right leg. Much more sporting than the column-mounted handle used on Powerglide passenger models, it was a step in the right direction. It also cut costs and complexity compared to the maze of links, pivots, and bell cranks that would have been required for a passenger-car-style column shifter, whether manual or automatic.

       Offsetting its stodgy Powerglide transmission, the first Corvette tapped into the cool factor, and utility, of a floor-mounted shift lever. All subsequent Corvettes shared this detail.

      54 To increase output from 115 to 150 hp for 1953 Corvette duty, the venerable 235-ci Blue Flame inline 6-cylinder engine was fitted with a trio of horizontally mounted (side draft) Carter YH carburetors, with high-flow split-outlet iron exhaust manifolds, full-length dual exhaust, a mechanical cam with .405/.414-inch lift (intake/exhaust), dual valvesprings, and aluminum 8.0:1 compression pistons to deliver 150 hp at 4,200 rpm and 223 ft-lbs of torque at 2,400 rpm. Unlike later years where certain Corvette engines were shared with passenger cars, the triple-carbureted 6 was not offered elsewhere.

      55 To achieve a respectable 53/47 (front/rear) static distribution of Corvette’s 2,850-pound curb weight, the engine and transmission were positioned 3 inches lower and a full 7 inches farther back in the chassis as compared to a Chevrolet sedan.

      56 The low-slung body shell hugged the top of the engine and called for a special rocker cover with a sloping leading end. The traditional upright radiator was too tall, so the expansion tank was separated and positioned alongside the engine’s rocker cover, on the passenger’s side. This began a long tradition of Corvette-specific cooling systems with remotely located radiator expansion tanks.

      57 A quick way to tell a 1953 Corvette 6 from a 1954–1955 unit is to check the valvecover hold-down bolts. First-year engines used two centrally mounted acorn nuts to secure the cover to the cylinder head, while 1954–1955 engines switched to four pan-head screws, positioned lower, around the flange meeting the cylinder head. The revised layout better clamped the gasket to prevent oil leaks. This valvecover and head redesign also applied to GM’s passenger cars and light trucks during the same time period.

       You’re kidnapped and the captors command you to tell a 1953 Corvette from a 1954 just by looking at the engine. Fact 57 could save your life.

      58 The 1955 Corvette stands as a transitional model. It wore the early body but stepped up to V-8 power. Although General Motors became conservative with production to ward off an inventory glut, all but 7 of the 700 1955 Corvettes easily bruised European sports cars thanks to the new 265-ci OHV V-8. Arkus-Duntov obtained one of the first V-8 Corvettes and presented it to his wife, Elfie, for daily use. It wore special silver paint and a central racing stripe. Silver didn’t join Corvette’s option list until the 1957 arrival of Inca Silver.

      59 Frugal buyers did not special-order the seven 6-cylinder Corvettes built in 1955. Rather, the St. Louis plant had leftover engines and had to “build them out” (as they say in the biz). It was up to dealers to find them homes. Still, buyers saved $135 ($2,774 versus $2,909 for the 195-hp 265 V-8). The seven 6-bangers carried VINs starting with E55. The new V-8s received VINs starting with VE55. In the 1978 Petersen Deluxe Series book Corvette: An American Classic, John Amgwert (of the National Corvette Restorer’s Society/NCRS) reported that five of the 6-cylinder 1955 Corvettes were still in existence at the time of publication, an amazing survival rate.

      60 The 1955 arrival of the 265 V-8 brought a superior 12-volt electrical system. That said, the handful of 6-cylinder Corvettes built retained the 6-volt electricals used in 1953 and 1954. This point was crucial during battery, generator, and lamp service and replacement. The 6-cylinder Corvettes were the only 6-volt passenger cars built by Chevrolet in 1955; everything else, even 6-cylinder taxicabs, were upgraded to 12-volt layouts that year.

      61 The Corvette’s fiberglass firewall was ineffective at preventing electronic energy from interfering with radio reception. To prevent energy released by the ignition distributor, spark plugs, and spark-plug wires from reaching the radio antenna, an elaborate, multi-piece, stamped-steel shield encased the ignition system on the passenger’s side of all 1953–1955 6-cylinder Corvettes.

      62 For 1953, the two-piece ignition-shield stamping was painted blue to match the rest of the engine. For 1954, chrome plating was added for extra eye appeal. However, as supplies varied, many cars were built with half of the shield rendered in chrome and the other half painted blue. There was no rhyme or reason to what was installed by the St. Louis assembly workers other than what was available at the moment. In today’s restoration world, most 1953–1954 Corvettes are shown with chromed shields despite the fact that chrome is incorrect for 1953 production models.

       Keeping a lid on radio static, this elaborate chamber encased the distributor and spark-plug wires. The chromed, remote expansion tank was separated from the radiator for hood clearance.

      63 When the 265-ci V-8 arrived in 1955, the radio interference issue was even more pronounced, as the distributor now sat less than 20 inches away from the radio receiver. Enclosing the distributor in a chrome-plated metal canister and adopting spark-plug wires with braided metal sheaths solved the problem. This was the first of several different shielding strategies applied to V-8 Corvette ignition systems through the successive years.

      64 Chevrolet had running V-8 engines on hand when the Corvette was introduced in 1953. However, they were preproduction forebears of the mighty 265-ci small-block engine that wouldn’t be ready until the 1955 model year. One of these experimental V-8s, with 231 ci, was installed in one of the 1953 Corvette Motorama show cars after its show duties were over. Delays in the official release of the small-block V-8 were the only factor preventing the Corvette from arriving with a V-8 power plant from the start.

      65 To improve acceleration, the Corvette-spec cast-iron Powerglide automatic was reprogrammed to remain in Low gear right up to 47 mph under full throttle and not to upshift from Low to Drive before 4,500 rpm. It was also set to kick down from Drive to Low gear at any speed below 50 mph.

      66 The Powerglide transmission used behind the new 265-ci V-8 shared the same 1.82:1 Low gear ratio as the Blue Flame 6 but had a different stall speed and improved friction faces to suit the increased torque. Because it lacked an intermediate gear ratio between Low (1.82:1) and Drive (1:1), flooring the gas pedal of any Powerglide Corvette at speeds below 50 mph resulted in a sudden jump in engine RPM that frightened some riders.

      67 An early spate of carburetor fires afflicting 1953 models triggered a redesign of the air-cleaner configuration. The trio of bullet-shaped units initially used could drip raw gasoline onto the hot exhaust manifolds below if flooded. To remedy this for 1954 and 1955, the three carburetor mouths were sealed to a horizontal tube that was fed clean air by two chromed circular filter units. A СКАЧАТЬ