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Rabu, 29 Februari 2012

A Brief Digression -- A Bad Crankshaft Position Sensor on my 2006 Nissan Spec V 2.5


Location of sensor taken from an engine out of the car. I am loathe to sell this vehicle right now, only because I recently bought new tires and a new battery for it. Never again will I own a Japanese car!

OK folks -- for about a week now the check engine soon light has been on and off on my 2006 Nissan Spec V 2.5 liter. I did an OBD-II scan and the instrument indicated a fault code for a crank position sensor fault. So I changed a sensor on the cam, close to the top of the engine, and thought that was it. But No! There is a second sensor, just like the first, in a near uinaccessible place at the bottom of the engine near the transmission. So this is what I am about to work on during our two day "Spring break", starting tomorrow morning. Pray for me, as I will need God's help to fix this.
John

Aerodynamics and the Automobile -- a Brief History Concerning the Path of Least Resistance







Streamlining and the Chrysler “Airflop”



As articulated previously, James Flink’s argument concerning technological stagnation during the interwar years is open to revision. For example, James Newcomb has argued that in terms of shape and design, the 1930s “represent a period of the most pronounced transition in automobile styling.”15 Newcomb argues that beginning with the1931 Reo Royale and the Chrysler Airflow, rounder, smoother, and more flowing shapes gradually were introduced, and that this was due to cultural constructs that emphasized security and togetherness at the expense of individualism. In sum, it was a shift in values tied to a Depression-era culture in transition that became expressed in the way cars looked. Consequently, the automobiles of 1940 in no way resembled the automobiles of 1929, just as the America of 1940 was far different than that prior to the Great Depression.
One prominent example illustrating Newcomb’s argument is the story of the development of the Chrysler Airflow and work in streamlining and aerodynamics in general that occurred in the automobile industry. Throughout the 1920s and 1930s, there was considerable enthusiasm for aviation, and some of it spilled over into automotive areas. Indeed, the relationship between the automobile industry and aviation remains to be studied beyond superficialities. As previously mentioned, the dashboard of the Cord 810 resembled that found in aircraft of the day. Supercharging, developed at Wright Field in Dayton, Ohio, was installed in 1930s Mercedes and Auburn-Cord-Duesenberg models. But the rise in interest in automobile aerodynamics was also due to increases in engine size and horsepower, coupled with improved roads. The drag of a vehicle was responsible for both lower top speeds and higher fuel mileage.
One of the first individuals to explore the aerodynamics of the automobile beyond a theoretical discussion was Edmund Rumpler, who constructed his Tropfenwagen (a car the shape of a water drop) in 1921.16 The Tropfenwagen can be translated as teardrop car, or raindrop car. Rumpler’s idea was that a falling drop of liquid was nature’s perfect airfoil design. As a drop fell, it would react to the pressure around it, and in so doing, its contour minimized wind resistance or drag. Only a limited number of these vehicles were built in 1921 and 1922, and then Rumpler sold the patents to the Benz firm. A surviving example of this historical curiosity can be found in the Technical Museum in Munich.
It is unclear what if any influence Rumpler had on the thinking of American automobile engineers, but technical articles appearing in the 1930s suggest that Paul Juray’s work was noticed and carefully studied in the U.S.17 The Hungarian-born Jaray was chief of the development department of the Zeppelin Airship works between 1914 and 1923. During the spring of 1921 he studied air flow passing around car bodies by using one-tenth scale wood models at the Zeppelin facility in Friedrichshafen, Germany. Jaray concluded that the vertical longitudinal section of a car was most important, and that it must be designed in such a way as to guide the air flow up and over the car in the front and down in the rear in such a manner that minimizes turbulence.
Others were thinking along similar lines during the late 1920s, and certainly one important figure was that of Carl Breer. As previously discussed, Breer, along with Owen R. Skelton and Fred Zeder, were known as the Three Musketeers at Chrysler Corporation during the 1920s. The three had formed a consulting engineering firm in 1921 after working for at time at Studebaker, and it was then that they caught the attention of Walter Chrysler. In 1924 they were instrumental in designing the Chrysler Model 70. As the story goes, Breer conceived of the Airflow concept while driving to his summer home in 1927. Traveling near Selfridge airfield, he spotted what he first thought was a flock of geese flying overhead, only to find it was a squadron of Army Air Corps planes on maneuvers. Aviation was on the minds of many Americans in 1927, as it was in May of that year that Charles Lindbergh flew solo across the Atlantic, and a new era of commercial aviation was just beginning. At any rate, this insight, and his playful inquisitiveness involving the forces of air resistance to an arm extended outside his car’s window led Breer to ponder ideas that were being discussed much of the time, namely that of form following function that had roots in the writing and architectural work of Louis Sullivan and his far more famous pupil, Frank Lloyd Wright. The question that remained in 1927 was “Why were aircraft becoming more streamlined while cars remained little more than boxy carriages?”
Approaching the problem scientifically, Breer went to William Earnshaw, an engineer at a research laboratory in Dayton, Ohio, and provided him with a car for making measurements of air-pressure lift and distribution. He also talked with Orville Wright, who assisted Earnshaw in designing a small wind tunnel where Breer subjected various scale models consisting of blocks of different shapes to aerodynamic analysis. With the addition of smoke, airflows passing around the models could be studied in the wind tunnel. As Earnshaw discovered from these experiments, areas of lower pressure formed behind the model, and higher pressures in the front. By rounding the front of the design and tapering the rear, streamlining was achieved.18
Before long, Walter Chrysler became interested, and approved construction of a much larger wind tunnel at Highland Park, Michigan, where over the next three years researchers tested hundreds of shapes, plotted eddy curves, noted turbulence, checked wind resistance, and calculated drag numbers.19
In addition to Chrysler engineers, there were others working on streamlining at this time. Most significantly, Amos E. Northrup, who worked for the Murray Body Company, designed the 1932 Blue Streak Graham with its enclosed fenders and radiator cap under the hood. A few others had more radical solutions, especially Buckminster Fuller with his Dymaxion car.20
Fuller, one of the true design geniuses of the twentieth century, is better known for his geodesic dome structure that was first proposed in 1949. In 1928, during a period of intense study, Fuller wrote a 2,000 page essay he called 4-D, and it was from the ideas articulated in this essay that the Dymaxion car emerged. Fuller designed his streamlined automobile in an abandoned Locomobile factory located in Bridgeport, Connecticut. The first Dymaxion was produced in 1933 from plaster models, and demonstrated at the Chicago Century of Progress World’s Fair. It was a gleaming, aluminum bullet-shaped object powered by a standard Ford V-8, and it was capable of going 115 mph. It brought together submarine and dirigible shapes, and there was nothing like it on the road. In this car the driver sat in the front, and there was no long hood. Shatterproof aircraft glass wrapped around the front, and sticking through the roof was a rear periscope. It was a low-slung vehicle that resembled a wingless fish and rode on just three wheels, two in the front and one in the rear. The two front wheels provided traction and braking and the rear steering. So many new ideas went into that transport: front wheel drive, air-conditioning, recessed headlights, and a rear engine. But an unfortunate accident killed the novel vehicle, even though it was not its fault, and its major idea, streamlining, was captured by the 1934 Chrysler Airflow.
In the six years that Breer and his team spent on the Airflow project, many trial and error experiments were performed that discovered some of the practical the rules of aerodynamics. One of the conclusions suggested a modified teardrop shape that allowed for a windshield and hood.21 The Airflow was an “engineers car,” with a conventional front engine rear and drive layout, but with some important modifications. Its engine was moved some 20 inches ahead of its normal position, front end styling characterized by a short curved nose, and an integral trunk. The fuel tank and radiator were now concealed. Inside, the center latch doors were chair-height seats in a vast, spacious interior. Riders sat at almost the center of the car's balance, producing an effect described in one brochure as “Floating Ride.” Indeed, “Floating Ride” was the consequence of Breer’s insights concerning the natural rhythms of the human body and the periodic oscillations that automobiles developed because of spring height. “No matter whether you are sitting in the front seat or the back, you can relax completely and utterly . . . you can ride comfortably amidships . . . experience no bumping, bouncing or vibration of any kind. The bumps seem to flow under the car without reaching you.” Also missing from the Airflow was the typical wood and steel composite body common to virtually all other cars of the period. In its place was one complete unitized steel unit “built like a modern bridge.” Streamlining was thus achieved not only on the outside of the car, but structurally as well. Box girders ran longitudinally up from the front and were joined with vertical and horizontal members to create an exceptionally strong structure, supposedly 40 times more rigid than the conventional frame and body. With the rear seat moved 24 inches inward, and the engine now positioned immediately above the front axle, driver and passengers no long experienced the same levels of fatigue as those riding in traditionally-designed vehicles.
For all of the Airflow's virtues, many buyers just couldn't ignore its new shape. In retrospect, it was probably too different for the general public to accept. The most controversial elements were probably the rounded snout with its waterfall grill, plus slabbed sides and the spatted rear wheel openings. After its introduction in 1934 and public criticisms, modifications were made to the 1935, ‘36 and ‘37 designs, including changing the shape and size of the grill to the point where by the end of the production run, it appeared to take on a conventional appearance.22
Despite these attempts to earn public acceptance, the critics were unforgiving and unrelenting. Industrial designer Henry Dreyfuss claimed that the Airflow was a “case of going too far too fast.” Frederick Lewis Allen, editor of Harper's Magazine, described it as being “so bulbous, so obesely curved as to defy the natural preference of the eye for horizontal lines.” Because of lengthy retooling delays, the car was late coming off the line and there were rumors of it being a lemon. GM didn't help by orchestrating a smear campaign and introducing its own turret-top all steel roof automobiles in 1935. And certainly early models were plagued with flaws, as line workers had difficulty making this very new kind of car.
Chrysler responded with publicity stunts like that of Citroen where a car was dropped off a 110-foot cliff. The Airflow’s doors opened easily; it then started under its own power and was driven away. Beginning in 1935, Chrysler made outward design changes and entered the car in various endurance motor sport events. But the damage was done, and the cars would not sell. Beginning with only 12,000 units sold in 1934, the numbers continued to slide though 1937 before it was discontinued after 1938. More conventional models and a conservatively revised Airflow design called Airstream saved the company, but the whole episode is a case study in what rumors will do to undermine a technologically advanced product. From innovative leader to conservative follower, Chrysler emerged from the Airstream episode badly shaken, reluctant to take on major changes given what could happen. Throughout the 1940s, and indeed into the 1950s Chrysler was content to follow GM designs, the third of the Big Three. Chrysler’s executives were well aware that it could be trampled by the large paws of GM if it went in too bold a technological direction.
The story of aerodynamics and the automobile industry during the 1930s had a happier ending at the Ford Motor Company. It was at Ford during the late 1930s that John Tjaarda, a Dutch-born designer who had studied aerodynamics in England and served in the Dutch air force, designed the Lincoln Zephyr. The Lincoln Zephyr’s drag coefficient was lower than that of the Airflow, as was its weight. Dr. Alexander Klemin, one of the designers of the Airflow, had miscalculated and made the Airflow’s body twice as strong as it had to be.
Drag and aerodynamics were for the most part ignored in the U.S. even after World War II, the one exception being the abortive Tucker of the late 1940s. In Europe, however, car companies that included Citroen, Volkswagen, and Fiat did pay attention to aerodynamics. It was only after the 1973 fuel shock that computer-aided design and computer-aided engineering were harnessed to improve the streamlining of autos, since fuel efficiency is intimately connected with drag. Thus, it was 40 years after Carl Breer at Chrysler had made the bold move to study aerodynamics at Chrysler that the industry caught up.23 In the process, the engineer and the stylist were now together in terms of their functions, and thus the stylist of old, artists the likes of Harley Earl, gave way to a new type of professional in the auto industry working in the 1980s.

Selasa, 28 Februari 2012

Cars I Love 2 -- Porsche 356




Hi folks -- some of you know that I have a 1971 Porsche 911T targa that I have obsessed over for many years and resurrected from the "grave." Where did I get this love of the Porsche brand? Certainly not from my father who was the owner of many Chevys. My older cousins did not like foreign cars. I can trace it back to the above photographed toy, a Ditzler Porsche 356, of which I owned one as a child, in this color Cerulean blue. My aunt and uncle, who lived in Hambach, Germany,bought me a number of neat presents during the 1950s, I think in part to pay my parents back for the many packages they sent during the lean times after WWII. This particular toy had a cable controlled steering mechanism you could hook up, and if I remember correctly, some sort of floor shifter. I played with this toy for hours, and now wish I owned a light blue 356 instead of the 911. Any takers for a trade?

Photo of 1946 Packard, Texaco Station, Cafe and Cabins -- Courtesy of Michael Kenny




Hi folks- this is the photo that included the mystery car -- the 1946 Packard -- from a previous post. Note the very interesting architecture of the station. Does anyone know where this may have been taken? Thanks to Michael Kenny!

Minggu, 26 Februari 2012

Ed Garten Wins Photo Puzzler -- It is a 1946 Packard!!



John, I believe the mystery car to be a 1946 Packard. Look at the attached photo of a 46 Packard rear end.

1. Packard used a diagonal script on the left hand side of the rear deck that said "Packard" -- this photo and your photo indicate the diagonal script.
2. The rear window shape is the same in both photos and the curvature of the trunk lid appear to be the same.
3. The bumper appears to be the same in both photos.
4. While a number of makes and models used rectangular taillights on the lower edges, both of these photos indicate similar shaped tail lights.
5. The trunk handle on the 46 Package hung straight down and was a very heavy fixture like on the mystery car.

But I could be wrong. My first guess was a Hudson, Nash, or Olds but checking photos on Google lead me eventually to the Packard.

Ed

1948 Mystery Car!! Can you Identify This???



Help me here! Mike Kenny sent me this asking for make model and year -- maybe a 1948. Can someone step to the plate and provide fill in the right information? I will send the winner a mystery Porsche part as a momento of your service.

Sabtu, 25 Februari 2012

Cars I Love 1: Mercedes-Benz 300SL Roadster

Hi folks -- last night at a party someone asked me what would be the one car I would have above any other?" The expectation was that I would reply with something like "Duesenberg." But the German in me came through, or perhaps the influence of my cousin Freddy, who when I was quite young and he was much older -- 17 years older to be precise -- stated the M-B 300 SL. I am pretty sure that Freddy was thinking of the Gullwing model, but since i ma a top-down kind of guy, I have always preferred the roadster. So if my wife Kaye ever dies, it is sell the house, liquidate some assets, and buy one of these come hell or high water!

New York Mercedes distributor Max Hoffman, Daimler-Benz's official importer in the USA, suggested to DBAG management in Stuttgart that a street version of the 300SL would be a commercial success, especially in America.

The racing W194 300SL was built around a tubular chassis to offset its relatively underpowered carbureted engine. Designed by DBAG's chief developing engineer, Rudolf Uhlenhaut the metal skeleton saved weight while still providing a high level of strength. Its unique architecture gave birth to the model's distinctive gull wing doors, as part of the chassis passed through what would be the lower half of a standard door. Even with the upward opening doors, the 300SL had an unusually high sill, making entry and exit from the car's cockpit problematic. A steering wheel with a tilt-away column was added to improve driver access.

The 300SL's body was mainly steel, except for the aluminum hood, doors and trunk lid. It could also be ordered with an all-aluminium outer skin at tremendous added cost, saving 80 kg (176 lb).

More than 80% of the vehicle's total production of approximately 1400 units were sold in the US, making the Gull wing the first Mercedes-Benz which sold in bulk outside its home market and confirming the validity of Hoffman's suggestion. The 300SL is credited for changing the company's image in America from a manufacturer of solid, but staid, automobiles to that of a producer of sporty cars.

1955 Mercedes-Benz 300SL Gullwing Coupé from the Ralph Lauren collection
1957 Mercedes-Benz 300SL Roadster
1956 300 SL
1956 "Gull wing" open

The 300SL's engine, canted at a fifty-degree angle to the left to allow for a lower hoodline, was the same 3.0 liter straight 6 as the regular four-door 300. Fitted with a Bosch mechanical Gasoline direct injection system it had almost double the power of the original 86 kW (115 hp) carbureted version.

While not the first fuel-injected car - Mercedes engineers who had developed the principle for the DB 601 fighter aircraft engine had used fuel injection in the tiny 2-stroke Gutbrod they had designed after the War - it was the first to inject fuel directly into the cylinders. This innovation allowed a top speed of up to 260 km/h (161 mph) depending on gear ratio and drag, making the 300SL the fastest production car of its time.

The engine's maintenance requirements were high. Unlike the current electrically powered fuel injection systems, the mechanical fuel pump would continue to inject gasoline into the engine during the interval between shutting off the ignition and the engine's coming to a stop; this gasoline was of course not burned, and washed the oil from the cylinder walls and ended up diluting the engine's lubricating oil, particularly if the engine was not driven hard enough nor long enough to reach a temperature high enough to evaporate it out of the oil.

Exacerbating the problem were the large oil cooler as well as the large volume of oil (10 liters), both oriented more to racing than to street driving, which virtually guaranteed that the oil would not reach a high enough temperature. In practice, many street drivers would block off airflow through the oil cooler, and the recommended oil change interval was 1,000 miles (1,600 km). Operation of the clutch was initially very heavy, later roadsters having an improved clutch arm helper spring which reduced the pedal force. From March 1963 to the end of production, a light alloy crankcase was used on a total of 209 vehicles.[2]

Aerodynamics played an important role in the car's speed, Mercedes-Benz engineers even placing horizontal "eyebrows" over the wheel openings to reduce drag. Unlike many cars of the 1950s, the steering was relatively precise and the four-wheel independent suspension allowed for a reasonably comfortable ride and markedly better overall handling. However, the rear swing axle, jointed only at the differential, not at the wheels themselves, could be treacherous at high speeds or on imperfect roads due to extreme changes in camber. The enormous fuel tank capacity caused a considerable difference in handling depending on the quantity of fuel on board.