Born in France, nurtured in America, the V-8 has satisfied the power hungry for a century.
Blame French communications engineer and aero-engine designer Clément Ader.
In 1903, this enterprising fellow hoped to make a name for his Société Industrielle des Téléphones-Voitures Automobiles Système Ader by entering a fleet of seven cars in the Paris-to-Madrid road race. His squadron consisted of one V-2, three V-4s, and three V-8 automobiles. Ader's first V-8s were created by lashing together two V-4s.
Unfortunately, the race was an epic disaster. The starting grid consisted of more than 200 cars and several auto pioneers: Charles Rolls, Vincenzo Lancia, and brothers Marcel and Louis Renault. News reports claimed that more than 100,000 spectators showed up for the 3:30 a.m. start at Versailles. Wild driving, dust, animals on the course, and mechanical failures quickly sent the hapless racers into ditches, trees, and unruly spectators. Over half the field crashed or broke down. More than 100 people were injured, and the death toll numbered at least five racers and three spectators.
One hundred or so cars did make it to Bordeaux, where the field was flagged to a halt, loaded on rail cars, and ignominiously returned to Paris. After Marcel Renault succumbed to his injuries, journalists dubbed the event The Race to Death.
Remarkably, all of Ader's cars completed the 340-mile trek to Bordeaux. That success sparked interest in V-8 engines, and more soon followed. Two years later, Frenchman Alexandre Darracq built a lusty 22.5-liter OHV V-8 to power a racer driven by Victor Héméry. In 1905, this concoction set a land-speed record of 110 mph in southern France. Later, Louis Chevrolet demonstrated the same car in America.
In 1906, yet another Frenchman, Léon Levavasseur, presented a light, compact aircraft V-8 in a car at the Paris salon. Antoinette in France and Adams in England produced and sold a few such automobiles with this design.
The quest for V-8s shifted to America in 1907 when aviation pioneer Glenn Curtiss upped the land-speed record to 136 mph with what he called a motor bicycle at Florida's Ormand Beach.
Back in France, De Dion–Bouton began selling the first series-produced V-8 automobiles in 1910. At least a dozen different V-8 engine designs were built and sold over the next 14 years. Stripped for speed, examples of these V-8 cars finished fourth in Sicily's 1913 and 1914 Targa Florio.
CADILLAC CHIMES IN
In 1910, under Henry Leland's capable guidance and General Motors' benevolence, Cadillac was the seventh-bestselling U.S. nameplate with a line of cars powered by a 33-hp four-cylinder engine. A half-dozen competitors had already moved to sixes for their top models. Not all were successful, but it was clear that something better than a four-cylinder engine would be necessary for Cadillac to sustain its Standard of the World status.
In 1912, Cadillac introduced self-starting to supplement its highly successful Delco ignition system initiated two years before on its Model Thirty.
Thinking ahead, Henry's son Wilfred Leland proposed leapfrogging the competition with eight cylinders. Although the term benchmarking didn't exist yet, his engineering team purchased two V-8s for analysis: one by De Dion–Bouton and a Hall-Scott aero engine.
Toiling in a skunkworks, the brilliant Charles Kettering and Edward Deeds (former Delco partners) constructed their prototype V-8–powered car, which was sufficiently impressive to earn production approval from the Lelands. Engineer D'Orsay White, who brought high-speed-engine experience from Britain to Cadillac, was placed in charge of the development effort.
The resulting Cadillac Type 51 V-8 introduced for 1915 models was a 90-degree L-head design with intake and exhaust manifolds contained between the cylinder banks. (In today's vernacular, this would be a hot- and cold-V design.) Each head and block of four cylinders consisted of one iron casting bolted to an aluminum-copper-alloy crankcase. A 3.125-inch bore and a 5.125-inch stroke yielded 314 cubic inches. A single Cadillac-made updraft carburetor fed all eight cylinders. The dual breaker-point and coil ignition system was reliable to 4000 rpm. A motor-generator provided electric starting and lighting energy.
Features drawn from the aforementioned French V-8 were a chain-driven camshaft with but eight lobes and roller rockers to actuate the valves. The crankshaft was supported by three main bearings; a knife-and-fork connecting-rod arrangement avoided offset cylinder banks.
To support high-speed operation, Cadillac engineers added efficient exhaust ports and cooling passages; two water pumps equipped with thermostatic valves restricted coolant flow during warm-up. Ages before Ferrari discovered the benefits of a single-plane 180-degree crankshaft, Cadillac incorporated such a configuration in its first V-8.
A smooth 70 horsepower was provided at 2400 rpm and cruising up to 65 mph (roughly 2800 rpm) was possible. The new Cadillac V-8 was a huge success with 13,000 sales in 1915, prompting more than 20 other brands to follow with their own V-8 designs by 1920.
A larger intake manifold was installed for 1916, and two such 77-hp Type 53 Cadillacs averaged more than 70 mph in a 100-mile test conducted by the Automobile Club of America. In May 1916, the great Cannonball Baker and writer William Sturm broke their Los Angeles to New York record by nearly four days, averaging 463 miles per day in a Cadillac V-8 roadster. During World War I, Cadillacs were the preferred car for transporting U.S. and foreign officers; more than 2000 were shipped overseas, including a 1918 Type 57 that was added to the National Historic Vehicle Register this week. In an ironic move, the Lelands left Cadillac in 1917 to manufacture Liberty aircraft engines in a new organization dubbed . . . the Lincoln Motor Company.
An important improvement for the 1924 model year was Cadillac's introduction of the first 90-degree, two-plane crankshaft. This eliminated secondary shaking forces that cause the engine to rock on its mounts. (Removable cylinder heads had been introduced for 1918.)
A second-generation, 341-cubic-inch V-8 arrived for 1928 with side-by-side connecting rods, improved lubrication, and a single water pump. With a 3.31-inch bore, 4.94-inch stroke, and a higher compression ratio, this engine delivered 90 horsepower at 3000 rpm.
Cadillac integrated block and crankcase components in a single casting in 1936. Three main bearings were still in use, and a two-barrel downdraft carburetor was added. Output climbed to 135 horsepower. Shortly after an automatic transmission became available in 1941, car production ceased and Cadillac supplied V-8 engines for the M-5 light tanks that it constructed for World War II use.
By then work had commenced on a modern overhead-valve V-8 engine to take advantage of higher-octane gasoline and rising road speeds. The new design was introduced for the 1949 model year with a 3.81-inch bore and 3.63-inch stroke yielding 331 cubic inches and 160 horsepower at 3800 rpm. Cast iron was used for the block and heads. The crankshaft was now supported by five main bearings. The new valvetrain had overhead rocker shafts and hydraulic lash adjusters. Cars equipped with Cadillac's new V-8 finished third, tenth, and eleventh at the 1950 24 Hours of Le Mans. That year Cadillac topped 100,000 sales for the first time.
Cadillac was strong during the 1950s horsepower race: 250 in 1955 and 270 with dual four-barrel carburetor Eldorados. In '57, larger displacement and higher compression upped the ante to 300 horses in standard models and 325 in Eldos. A longer stroke for 1959 increased displacement to 390 cubic inches and 345 horsepower with three two-barrel carburetors.
Trimming weight was the goal throughout the 1960s. A new 429-cubic-inch V-8 for 1964 was lighter than the 1949 design while delivering 340 horsepower. A 1968 redesign brought 472 cubic inches, the first emissions controls, and 525 lb-ft of torque at 3000 rpm. Two years later, a 500-cubic-inch V-8 for the front-drive Eldorado delivered a nice, round 400 horsepower.
In pursuit of lower emissions, Cadillac innovated electronic ignition in 1974, followed by fuel injection and catalytic converters in 1975. This division was also ahead of the curve with its modulated displacement V-8-6-4 engine in 1981; unfortunately, it lacked today's electronic controls and was a dismal failure.
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Only a year later, the more carefully engineered High Technology 4.1-liter V-8 was introduced with a die-cast aluminum block topped by cast-iron cylinder heads and digital electronic fuel injection. Output was a modest 125 horsepower at 4200 rpm. Further tuning yielded 200 horsepower at 4300 rpm from 4.5 liters in the 1989 Cadillac Allante.
Cadillac's illustrious 4.6-liter Northstar V-8 for the 1993 Allanté, Seville, and Eldorado boasted DOHC, four valves per cylinder, and aluminum-block and -head construction. The aluminum pistons and steel connecting rods were both forged for strength. Use of magnesium and molded-plastic castings helped trim weight. Electronic circuits regulated the port fuel injection and four ignition coils. A limp-home mode allowed the engine to run on four cylinders without damage after a total loss of coolant. With an initial rating of 295 horsepower, this roughly 400-pound engine had a production life lasting through the 2011 model year for front-drive Cadillacs. Adding a supercharger for 2006–2009 V-edition XLR and STS models raised output to 443 and 469 horsepower.
For the past quarter-century, Cadillac has also employed pushrod V-8s born at other GM divisions. Escalade trucks, for example, began with the Vortec 5700, adding the 6.2-liter Gen IV small-block in 2007. The Corvette's hot 5.7-liter LS6 V-8 brought 400 horsepower to the CTS-V for 2005; the supercharged LSA V-8 arrived there in 2009 with 556 horsepower. New-for-2015 Escalades have 420-hp 6.2-liter V-8s.
Among its V-8 models available during the layout's 2015 centennial, Cadillac is sending off the current CTS-V coupe with a run of 500 limited-edition cars. A CTS-V sedan is expected to rejoin the 2016 lineup with a supercharged 6.2-liter making at least 600 horsepower. While hot four-cylinder engines and twin-turbo V-6s are clearly the future, Cadillac has no intentions of saying goodbye to its long-loved V-8 anytime soon.
from Car and Driver Blog http://ift.tt/nSHy27
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