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127-461: The 1973–1976 Chevelle Lagunas accounted for 108,815 of nearly 1.7 million third generation Chevelle sales. Production included 42,941 1973 Laguna coupes, and 38,790 1974–1976 Laguna Type S-3 coupes, making them relatively rare cars in today's collector market. Chevrolet honored California beach resorts again by naming the top 1973 Chevelle series "Laguna" with the Malibu taking the middle spot while

254-414: A countershaft (also called a layshaft ) and an output shaft . The input shaft is connected to the engine and spins at engine speed whenever the clutch is engaged. The countershaft has gears of various sizes, which are permanently meshed with the corresponding gear on the input shaft. The gears on the output shaft are also permanently meshed with a corresponding gear on the countershaft; however,

381-595: A bumper standard that yields the "maximum feasible reduction of cost to the public and to the consumer". Factors considered included the costs and benefits of implementation, the standard's effect on insurance costs and legal fees, savings in consumer time and inconvenience, as well as health and safety considerations. The 1973 model year passenger cars sold in the U.S. used a variety of designs. They ranged from non-dynamic versions with solid rubber guards, to "recoverable" designs with oil and nitrogen filled telescoping shock-absorbers. The standards were further tightened for

508-642: A car's safety systems must still function normally after a straight-on pendulum or moving-barrier impact of 4 km/h (2.5 mph) to the front and the rear, and to the front and rear corners of 2.5 km/h (1.6 mph) at 45.5 cm (18 in) above the ground with the vehicle loaded or unloaded. European countries have implemented regulations to address the issue of 270,000 deaths annually in worldwide pedestrian/auto accidents . Specialized bumpers, known as " bull bars " or "roo bars", protect vehicles in rural environments from collisions with large animals. However, studies have shown that such bars increase

635-708: A column shifter and more practical, as the gearbox was mounted in front of the engine. The linkage for the shifter could then be positioned on top of the engine. The disadvantage is that shifting is less comfortable and usually slower to operate. Newer small cars and MPVs , like the Suzuki MR Wagon , the Fiat Multipla , the Toyota Matrix , the Pontiac Vibe , the Chrysler RT platform cars,

762-417: A column shifter are the ability to switch between the two most commonly used gears—second and third—without letting go of the steering wheel, and the lack of interference with passenger seating space in vehicles equipped with a bench seat . Some smaller cars in the 1950s and 1960s, such as Citroën 2CV , Renault 4 and early Renault 5 feature a shifter in the dash panel. This was cheaper to manufacture than

889-527: A column-mounted manual shifter. Outside North America, the column-mounted shifter remained in production. All Toyota Crown and Nissan Cedric taxis in Hong Kong had the 4-speed column shift until 1999 when automatic transmissions were first offered. Since the late 1980s or early 1990s, a 5-speed column shifter has been offered in some vans sold in Asia and Europe, such as Toyota Hiace , Mitsubishi L400 and

1016-407: A conventional manual transmission, but are shifted automatically. Alternatively, there are semi-automatic transmissions . These systems are based on the design of, and are technically similar to, a conventional manual transmission. They have a gear shifter which requires the driver's input to manually change gears, but the driver is not required to engage a clutch pedal before changing gear. Instead,

1143-418: A flow-through power ventilation system, an inside hood release, a refined Delcotron generator and a sealed side-terminal battery, a larger, 22 gallon, fuel tank, and "flush and dry" rocker panels introduced first on the redesigned 1971 full-size Chevrolets. Another structural improvement was a stronger design for the side door guard beams. Options included swiveling Strato- bucket seats (with console) for coupes,

1270-456: A front stabilizer bar , and HR70x15 radial tires on Rally wheels . Front occupants rode in swivel bucket seats, and the driver faced a six-dial instrument cluster and a four-spoke, sport steering wheel. The 1974 Laguna S-3 had replaced the discontinued "SS" as the performance option on the Chevelle. Production totaled 15,792 cars, with prices starting at $ 3,723 - and plenty of options to send

1397-411: A gear while the transmission requires the driver to adjust the throttle so that the transmission is not under load, and selecting a gear requires the engine RPM to be at the exact speed that matches the road speed for the gear being selected). Most motor vehicles use a pedal to operate the clutch; except for motorcycles, which usually have a clutch lever on the left handlebar . In most vehicles with

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1524-425: A gearshift without fully disengaging the clutch). Larger differences in speed between the input shaft and the gear require higher friction forces from the synchromesh components, potentially increasing their wear rate. Even in modern transmissions where all of the forward gears are in a constant-mesh configuration, often the reverse gear uses the older sliding-mesh ("crash box") configuration. This means that moving

1651-540: A lot to recommend it. The car has a very tight feeling, a by-product of the heavily ribbed underbody and double paneled roof. Strongly in the Laguna's favor is the integrated, body-colored urethane bumper-front end. It's a lot better looking out-front than the big bumper approach." Car and Driver said: " Directional stability is so strong on the highway that the Laguna seems locked on some guidance-beam radiated from your destination." "The Laguna's urethane nose cap allows

1778-619: A manual transmission but have added components (such as computer -controlled actuators and sensors ) which automatically control the timing and speed of the gear shifts and clutch; this design is typically called an automated manual transmission (or sometimes a clutchless manual transmission ). Contemporary manual transmissions for cars typically use five or six forward gears ratios and one reverse gear, however, transmissions with between two and seven gears have been produced at times. Transmissions for trucks and other heavy equipment often have between eight and twenty-five gears, in order to keep

1905-438: A manual transmission, the flywheel is attached to the engine's crankshaft , therefore rotating at engine speed. A clutch disc sits between the flywheel and the transmission pressure plate which is attached to the transmission input shaft, controlling whether the transmission is connected to the engine or not. The clutch pedal controls the pressure plate ( clutch engaged – the clutch pedal is not being pressed) or not connected to

2032-421: A manual transmission, the driver selects gears by manipulating a lever called a gear stick (also called a gearshift , gear lever or shifter ). In most automobiles, the gear stick is located on the floor between the driver and front passenger, but some cars have a gear stick that is mounted to the steering column or center console. The movement of the gear stick is transferred (via solid linkages or cables) to

2159-400: A mechanism is needed to stop the input shaft, such as using the synchronizer rings for fifth gear. However, some vehicles do employ a synchromesh system for the reverse gear, thus preventing possible crunching if reverse gear is selected while the input shaft is still spinning. Most transmissions include a lockout mechanism to prevent reverse gear from being accidentally selected while the car

2286-560: A moderate-speed collision. Around 500 people are killed this way in the United States annually. Following the June 1967 death of actress Jayne Mansfield in an auto/truck accident, the U.S. National Highway Traffic Safety Administration recommended requiring a rear underride guard, also known as a "Mansfield bar", an " ICC bar", or a "DOT (Department of Transportation) bumper". These may not be more than 22 in (56 cm) from

2413-460: A plastic cover over a reinforcement bar made of steel, aluminum, fiberglass composite, or plastic. Bumpers of most modern automobiles have been made of a combination of polycarbonate (PC) and acrylonitrile butadiene styrene (ABS) called PC/ABS. Bumpers offer protection to other vehicle components by dissipating the kinetic energy generated by an impact . This energy is a function of vehicle mass and velocity squared . The kinetic energy

2540-639: A power moonroof, and Turbine I urethane (backed by steel) wheels, as was the instrument gauge cluster. While lesser Chevelles (except the Malibu SS option) came standard with either a 250-cubic-inch six-cylinder or a 307-cubic-inch two-barrel V8, Lagunas came standard with a 145-horsepower 350-cubic-inch two-barrel V8. Options included a 350 four-barrel V8 of 175 horsepower (130 kW) and a 454 four-barrel V8 rated at 245 horsepower (183 kW). Hardened engine valve seats and hydraulic camshafts made these engines reliable for many miles, and allowed them to accept

2667-612: A proposal to upgrade the U.S. performance requirements for underride guards. Many European nations have also required side underride guards to mitigate lethal collisions where the car impacts the truck from the side. A variety of different types of side underride guards of this nature are in use in Japan, the US, and Canada. However, they are not required in the United States. UN Regulation 58 sets forth requirements for rear underrun protective devices (RUPDs) and their installation, among which

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2794-445: A revised grille and new parking lamps, augmented at the rear by new taillights . A federally-mandated 5 mph (8.0 km/h) chrome rear bumper replaced the body-colored steel 2.5 mph (4.0 km/h) version from 1973. Standard equipment included a console, a vinyl roof, opera-type vertical rear quarter windows which could be covered with horizontal ribs; body side striping, Laguna S3 badging, as well as firmer shocks and springs,

2921-426: A rigid construction and do not absorb (by plastic deformation) any energy in a collision, which is more dangerous for pedestrians than factory plastic bumpers. The legality of the aftermarket off-road bumpers varies by jurisdiction. Bumper regulations in the United States focus on preventing low-speed accidents from impairing safe vehicle operation, limiting damage to safety-related vehicle components, and containing

3048-552: A roll-over type accident. GM had anticipated federal roll-over safety standards for January 1974 that did not materialize. The unusually thin windshield pillars contributed to the much-improved visibility over the previous generation Chevelles. Two Laguna station wagons were introduced, including a Laguna estate . The wagons, available in six- or nine-passenger seating, featured a counterbalanced liftgate which allowed for easy entry and loading up to 85 cubic feet (2.4 m). The new top-of-the-line Laguna shared with all 1973 Chevelles

3175-441: A switch or pressing a button on the gearshift knob or on the steering column, or automatically by momentarily lifting the foot from the accelerator with the vehicle traveling above a certain road speed. Automatic overdrives were disengaged by flooring the accelerator, and a lockout control was provided to enable the driver to disable overdrive and operate the transmission as a normal (non-overdrive) transmission. The term 'overdrive'

3302-484: A synchromesh and teeth on each side in order to lock either gear to the shaft. Unlike some other types of clutches (such as the foot-operated clutch of a manual-transmission car), a dog clutch provides non-slip coupling and is not suited to intentional slipping. In order to provide smooth gearshifts without requiring the driver to manually match the engine revs for each gearshift, most modern passenger car transmissions use 'synchromesh' (also called 'synchronizer rings') on

3429-501: A third-place finish at Talladega Speedway in early May and never gave up the lead. He held off a late rally by Cale Yarborough to win by only 67.15 points. July 14, 1974: Volunteer 500-Cale Yarborough muscles his way around Buddy Baker on the final lap and squeezes out a narrow win in Bristol's Volunteer 500. It is the seventh win of the season for Yarborough and his No. 11 Chevelle. February 16, 1975: Daytona 500-Benny Parsons takes

3556-411: A three-speed manual transmission. This transmission, along with many similar designs that it inspired, was a non-synchronous (also called sliding-mesh ) design where gear changes involved sliding the gears along their shafts so that the desired cogs became meshed. The driver was therefore required to use careful timing and throttle manipulation when shifting, so the gears would be spinning at roughly

3683-439: A typical hydraulic automatic transmission , which uses an epicyclic (planetary) design, and a hydraulic torque converter . An automatic transmission that allows the driver to control the gear selection (such as shift paddles or "+/-" positions on the gear selector) is called a manumatic transmission, and is not considered a manual transmission. Some automatic transmissions are based on the mechanical build and internal design of

3810-498: A vehicle's bumper systems are designed to absorb the energy of low-speed collisions and help protect the car's safety and other expensive nearby components, most bumpers are designed to meet only the minimum regulatory standards. International safety regulations , devised initially as European standards under the auspices of the United Nations , have now been adopted by most countries outside North America. These specify that

3937-455: Is a structure attached to or integrated with the front and rear ends of a motor vehicle , to absorb impact in a minor collision, ideally minimizing repair costs. Stiff metal bumpers appeared on automobiles as early as 1904 that had a mainly ornamental function. Numerous developments, improvements in materials and technologies, as well as greater focus on functionality for protecting vehicle components and improving safety have changed bumpers over

Chevrolet Chevelle Laguna - Misplaced Pages Continue

4064-429: Is also used to describe a gear with a ratio of less than one (e.g., if the top gear of the transmission has a ratio of 0.8:1). Vehicles with a manual transmission can often be push started when the starter motor is not operational, such as when the car has a dead battery or when the starter motor itself has malfunctioned and is unable to deliver sufficient rotational energy to turn the engine over. When push-starting,

4191-427: Is connected via a pinion gear at the end of the counter/output shaft. In a modern constant-mesh manual transmission, the gear teeth are permanently in contact with each other, and dog clutches (sometimes called dog teeth ) are used to select the gear ratio for the transmission. When the dog clutches for all gears are disengaged (i.e. when the transmission is in neutral), all of the gears are able to spin freely around

4318-410: Is crucial that front bumpers be the first parts of a vehicle to make contact in the event of a frontal collision, to leave sufficient time to inflate the protective cushions. Energy-absorbing crush zones are completely ineffective if they are physically bypassed; an extreme example of this occurs when the elevated platform of a tractor-trailer completely misses the front bumper of a passenger car, and

4445-452: Is equal to 1/2 the product of the mass and the square of the speed. In formula form: A bumper that protects vehicle components from damage at 5 miles per hour must be four times as tough as a bumper that protects at 2.5 miles per hour, with the collision energy dissipation concentrated at the extreme front and rear of the vehicle. Small increases in bumper protection can lead to weight gain and loss of fuel efficiency . Until 1959, rigidity

4572-497: Is fielding an all-new intermediate Chevelle series at a time when competitive lines from Ford and Chrysler are one or more years old...when you look at what the stylists have done with what we used to call the pillar coupe, you might want to rush out and buy some stock in General Motors." Motor Trend said: "The Grand Am and the Laguna are large "small" cars. Nimble, quick and responsive." "The cleanly styled Laguna has

4699-445: Is moving forwards. This can take the form of a collar underneath the gear knob which needs to be lifted or requiring extra force to push the gearshift lever into the plane of reverse gear. Another design of transmission that is used in older cars , trucks , and tractors , is a non-synchronous transmission (also known as a crash gearbox). Non-synchronous transmissions use a sliding-mesh (or constant-mesh, in later years) design and have

4826-521: Is that trucks and trailers of various types must have such devices with height above the ground not more than 45 cm (17.7 in), 50 cm (19.7 in), or 55 cm (21.7 in). Mismatches between SUV bumper heights and passenger car side impact beams have allowed serious injuries at relatively low speeds. In the United States, NHTSA is studying how to address this issue as of 2014 . Beyond lethal interactions, repair costs of passenger car/SUV collisions can also be significant due to

4953-404: Is used to reverse the direction in which the output shaft rotates. In many transmissions, the input and output shafts can be directly locked together (bypassing the countershaft) to create a 1:1 gear ratio which is referred to as direct-drive . In a transmission for longitudinal engined vehicles (e.g. most rear-wheel-drive cars), it is common for the input shaft and output shaft to be located on

5080-542: The Chevrolet Monte Carlo starting in 1978, with significantly lower mass than heavy chromed-steel bumpers with separate impact energy absorbers. The bumper regulations applied to all passenger cars, both American-made and imported. With exceptions including the Volvo 240 , Porsche 911 , and Rolls-Royce Silver Shadow , European and Asian automakers tended to put compliant bumpers only on cars destined for

5207-674: The Honda Element , the Honda Civic , the Daihatsu Sigra , and the Honda Avancier , may feature a manual or automatic transmission gear shifter located on the vehicle's instrument panel, similar to the mid-1950s Chryslers and Powerglide Corvairs . Console-mounted shifters are similar to floor-mounted gear shifters in that most of the ones used in modern vehicles operate on a horizontal plane and can be mounted to

Chevrolet Chevelle Laguna - Misplaced Pages Continue

5334-517: The Southeastern 500 at Bristol. Yarborough leads all 500 laps. July 8, 1973: Volunteer 500-Points leader Benny Parsons drives his unsponsored Chevelle to an impressive win in the Volunteer 500 at Bristol International Speedway . Parsons finishes seven laps ahead of runner-up L.D. Ottinger . September 23, 1973: Wilkes 400- Bobby Allison runs down Richard Petty on the final lap to win

5461-427: The splines on the shaft, forcing that shaft to rotate at the same speed as the gear hub. However, the clutch can move back and forth on the shaft, to either engage or disengage the splines. This movement is controlled by a selector fork that is linked to the gear lever. The fork does not rotate, so it is attached to a collar bearing on the selector. The selector is typically symmetric: it slides between two gears and has

5588-415: The stereo system or HVAC system , to help prevent accidental activation or driver confusion. More and more small cars and vans from manufacturers such as Suzuki , Honda , and Volkswagen are featuring console shifters in that they free up space on the floor for other features such as storage compartments without requiring that the gear shift be mounted on the steering column. Also, the basic location of

5715-455: The "Phase I" standard. At the same time, a zero-damage requirement, "Phase II", was enacted for bumper systems on 1980 and newer cars. The most rigorous requirements applied to 1980 through 1982 model vehicles; 5-mile-per-hour (8 km/h) front and rear barrier and pendulum crash tests were required, and no damage was allowed to the bumper beyond a 3 ⁄ 8  in (10 mm) dent and 3 ⁄ 4  in (19 mm) displacement from

5842-451: The ('73) 350 Laguna. "... We couldn't pass up the opportunity to tell you what a groovy all around car it is even if it can't smoke the quarter-mile run in 13 seconds. And what car in '73 can." "It's not overpowering but it's enough - and so comfortable that the editor bought the car." "The Laguna is the type of car you want to own for fast, comfortable transportation in quiet luxury." Motor Trend - "1973 Buyers Guide" said: "Chevrolet

5969-471: The 1948 Ferrari 166 Inter and the 1953 Alfa Romeo 1900 Super Sprint . Five-speed transmissions became widespread during the 1980s, as did the use of synchromesh on all forward gears. Six-speed manual transmissions started to emerge in high-performance vehicles in the early 1990s, such as the 1990 BMW 850i and the 1992 Ferrari 456 . The first 6-speed manual transmission was introduced in the 1967 Alfa Romeo 33 Stradale . The first 7-speed manual transmission

6096-518: The 1950s, constant-mesh manual transmissions have become increasingly commonplace, and the number of forward ratios has increased to 5-speed and 6-speed manual transmissions for current vehicles. The alternative to a manual transmission is an automatic transmission . Common types of automatic transmissions are the hydraulic automatic transmission (AT) and the continuously variable transmission (CVT). The automated manual transmission (AMT) and dual-clutch transmission (DCT) are internally similar to

6223-424: The 1974 model year passenger cars, with standardized height front and rear bumpers that could take angle impacts at 5 miles per hour (8 km/h) with no damage to the car's lights, safety equipment, and engine. There was no provision in the law for consumers to 'opt out' of this protection. The regulations specified bumper performance; they did not prescribe any particular bumper design. Nevertheless, many cars for

6350-468: The 1975 Laguna had the 400 as the top engine. The 49-states' engine line-up was - the standard 145-horsepower 350 two-barrel V8, the optional 175-horsepower 400 four-barrel V8, and the 215-horsepower 454 four-barrel V8. In California, a 155-horsepower 350 four-barrel V8 was standard and the 180-horsepower 400 four-barrel V8 was the only engine option. All 1975 models included the newly introduced catalytic converter . The Turbo Hydra-matic three-speed automatic

6477-589: The Canadian requirements were not lowered to 4 km/h (2.5 mph) in 1982 as was done in the United States. Some automakers provided stronger Canadian-specification bumpers throughout the North American market, while others chose weaker bumpers in the U.S. market. This limited grey import vehicles between the U.S. and Canada. In early 2009, Canada's regulation shifted to harmonize with U.S. Federal standards and international UN Regulations . As in

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6604-559: The Malibu in pattern cloth and vinyl or optional breathable all-vinyl upholstery, distinctive door trim with map pockets, deep-twist carpeting, woodgrain vinyl accents, and Laguna nameplates. The 1973 Chevelle Laguna "Colonnade" hardtop featured a semi- fastback roofline with styled "B" pillars, frameless door glass and distinctive rear quarter glass on two-door coupes . New side windows with styled center pillars were featured on four-door sedan models. The new-design B pillars were structurally strong enough to contribute to occupant safety in

6731-474: The Monte Carlo SS) and louvered opera windows. The Colonnade designation was dropped. The vinyl half-roof, swiveling Strato-bucket front seats with center console, as well as the four-spoke sport steering were no longer standard S-3 equipment, and were made optional in mid-1974 to reduce the car's base price. The 454 engine option was available for the first half of the model year in the Chevelle and thus

6858-618: The Monte Carlo. Production of the Laguna edged up to 9,100 cars as the base price went to $ 4,621. The third generation Chevelle was an extensively used body style in NASCAR competition from 1973 to 1977. The Chevelle Laguna S-3 in particular was extremely successful. Its sloped nose, small rear quarter windows and "fastback-style" rear glass gave it an aero advantage over other GM body styles at NASCAR's fastest tracks. Junior Johnson's team, with driver Cale Yarborough, won 34 races and earned

6985-742: The Music City USA 420 at his hometown Nashville Speedway . Benny Parsons finishes second in his Chevelle. August 1976: Cale Yarborough drives his No. 11 Junior Johnson/Holly Farms Chevelle to the 1976 NASCAR Winston Cup Grand National championship. Yarborough won nine races along the way to the first of three consecutive titles. He finished last in the Daytona 500, but assumed command of the points chase in August. Yarborough beat Richard Petty by 195 points. February 20, 1977: Daytona 500-Cale Yarborough's Chevelle pulls away from Benny Parsons' Chevelle in

7112-533: The U.S. and Canada had a 3-speed column-mounted shifter—the first generation Chevrolet/GMC vans of 1964–70 vintage had an ultra-rare 4-speed column shifter. The column-mounted manual shifter disappeared in North America by the mid-1980s, last appearing in the 1987 Chevrolet pickup truck . Prior to 1980, the GM X platform compacts (Chevrolet Nova and its rebadged corporate clones) were the final passenger cars to have

7239-564: The U.S. and Canadian markets where the regulations applied. This meant their North American-spec cars tended to look different than versions of the same model sold elsewhere. U.S. bumper-height requirements effectively made some models, such as the Citroën SM , ineligible for importation to the United States. Unlike international safety regulations , U.S. regulations were written without provision for hydropneumatic suspension . The requirements promulgated under MVICS were consolidated with

7366-416: The U.S. market were equipped with bulky, massive, protruding bumpers to comply with the 5-mile-per-hour bumper standard in effect from 1973 to 1982. This often meant additional overall vehicle length, as well as new front and rear designs to incorporate the stronger energy-absorbing bumpers, adding weight to the extremities of the vehicle. Passenger cars featured gap-concealing flexible filler panels between

7493-529: The U.S., consumer protection groups opposed the change, while Canadian regulators maintained that the 4 km/h (2.5 mph) test speed is used worldwide and is more compatible with improved pedestrian protection in vehicle-pedestrian crashes . Manual transmission A manual transmission ( MT ), also known as manual gearbox , standard transmission (in Canada , the United Kingdom and

7620-466: The United States ), or stick shift (in the United States), is a multi-speed motor vehicle transmission system where gear changes require the driver to manually select the gears by operating a gear stick and clutch (which is usually a foot pedal for cars or a hand lever for motorcycles). Early automobiles used sliding-mesh manual transmissions with up to three forward gear ratios. Since

7747-547: The Wilkes 400 at North Wilkesboro Speedway. It was Allison's second win of the season in his No. 12 Chevelle. October 21, 1973: American 500-Benny Parsons pits for repairs after an early crash. The help of several teams allow him to get back into the race and finish 28th. Parsons and his Chevelle hold on to win the NASCAR Winston Cup Grand National championship. Parsons took the points lead with

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7874-622: The base series was called simply "Deluxe". Laguna models featured specific front and rear styling including a body-colored urethane front end concealing the new 5 mph bumper system. On minor impact the urethane nose cone, backed up by shock-absorbing cylinders, deflected and rebounded; Laguna models also featured a specific diecast chrome grille with bowtie emblem, a body-colored (steel) rear bumper , front and rear bumper rub strips, bright roof drip moldings, bright wheel-opening moldings, chrome taillight bezels, full wheel covers, and Laguna fender nameplates. Laguna interiors were more lavish than

8001-523: The bottom line past $ 5,000. Engine offerings included a standard 145 horsepower (108 kW) 350 two-barrel V8, with optional powerplants including a 150 horsepower (110 kW) 400 two-barrel V8, 175 horsepower (130 kW) 400 four-barrel V8 and 235 horsepower (175 kW) 454 four-barrel V8, except in California where a 155 horsepower (116 kW) 350 four-barrel V8 was standard and the 400 and 454 engines were optional. Turbo Hydra-matic transmission

8128-495: The bumper's original position. All-wheel-drive "cross-over" cars such as the AMC Eagle were classified as multi-purpose vehicles or trucks, and thus exempt from the passenger car bumper standards. The recently elected Reagan administration had pledged to use cost–benefit analysis to reduce regulatory burdens on industry, which impacted this standard. As discussed in detail under Physics , before 1959, people believed

8255-504: The bumpers and the car's bodywork causing them to have a "massive, blockish look". However, other bumper designs also met the requirements. The 1973 AMC Matador coupe had free-standing bumpers with rubber gaiters alone to conceal the retractable shock absorbers. "Endura" bumpers, compliant with the regulations yet tightly integrated into the front bodywork, were used on models such as the Pontiac Grand Am starting in 1973 and

8382-411: The clutch) or both of these functions are automated ). Most manual transmissions for cars allow the driver to select any gear ratio at any time, for example shifting from second to fourth gear, or fifth to third gear. However, sequential manual transmissions , which are commonly used in motorcycles and racing cars , only allow the driver to select the next-higher or next-lower gear. In a vehicle with

8509-484: The collar from bridging the locking rings while the speeds are still being synchronized. This is achieved through 'blocker rings' (also called 'baulk rings'). The synchro ring rotates slightly because of the frictional torque from the cone clutch. In this position, the dog clutch is prevented from engaging. Once the speeds are synchronized, friction on the blocker ring is relieved and the blocker ring twists slightly, bringing into alignment certain grooves or notches that allow

8636-463: The cone-shaped sleeve on the dog collar so that the friction forces can reduce the difference in rotational speeds. Once these speeds are equalized, the dog clutch can engage, and thus the new gear is now in use. In a modern gearbox, the action of all of these components is so smooth and fast it is hardly noticed. Many transmissions do not include synchromesh on the reverse gear (see Reverse gear section below). The synchromesh system must also prevent

8763-551: The corner crash test speeds from 3 miles per hour (5 km/h) to 1.5 miles per hour (2 km/h). In addition, the zero-damage Phase II requirement was rolled back to the damage allowances of Phase I. At the same time, a passenger car bumper height requirement of 16 to 20 inches (41–51 cm) was established for passenger cars. NHTSA evaluated the results of its change in 1987, noting it resulted in lower weight and manufacturing costs, offset by higher repair costs. Despite these findings, consumer and insurance groups decried

8890-513: The costs of repair after a crash. In 1971, the U.S. National Highway Traffic Safety Administration (NHTSA) issued the country's first regulation applicable to passenger car bumpers. Federal Motor Vehicle Safety Standard No. 215 (FMVSS 215), "Exterior Protection," took effect on 1 September 1972—when most automakers would begin producing their model year 1973 vehicles. The standard prohibited functional damage to specified safety-related components such as headlamps and fuel system components when

9017-438: The dog clutch to fall into the engagement. Common metals for synchronizer rings are brass and steel , and are produced either by forging or sheet metal shaping. The latter involves stamping the piece out of a sheet metal strip and then machining to obtain the exact shape required. The rings are sometimes coated with anti-wear linings (also called 'friction linings') made from molybdenum , iron , bronze or carbon (with

9144-427: The dog clutches require the input shaft speed to match that of the gear being selected; otherwise, the dog teeth will fail to engage and a loud grinding sound will be heard as they clatter together. Therefore, to speed up or slow down the input shaft as required, cone-shaped brass synchronizer rings are attached to each gear. When the driver moves the gearshift lever towards the next gear, these synchronizer rings press on

9271-413: The early 1950s, most cars only had synchromesh for the shift from third gear to second gear (drivers' manuals in vehicles suggested that if the driver needed to shift from second to first, it was best to come to a complete stop beforehand). Up until the late 1970s, most transmissions had three or four forward gear ratios, although five-speed manual transmissions were occasionally used in sports cars such as

9398-444: The ends of the vehicle, thereby increasing occupant protection from progressive crumpling in a serious accident. They are no longer made of steel and rubber, but of a plastic outer fascia over a lightweight, impact-absorbing polystyrene foam core. Automobile bumper standards in Canada were first enacted simultaneously as those in the United States. These were closely similar to the 8 km/h (5 mph) U.S. regulation, and

9525-407: The energy generated by the wheels moving on the road is transferred to the driveshaft, then the transmission, and eventually the crankshaft. When the crankshaft spins as a result of the energy generated by the rolling of the vehicle, the motor is cranked over. This simulates what the starter is intended for and operates in a similar way to crank handles on very old cars from the early 20th century, with

9652-435: The engine ( clutch disengaged – the clutch pedal is being pressed down). When the engine is running and the clutch is engaged (i.e., clutch pedal up), the flywheel spins the clutch pressure plate and hence the transmission. The design of most manual transmissions for cars is that gear ratios are selected by locking selected gear pairs to the output shaft inside the transmission. This is a fundamental difference compared with

9779-456: The engine speed within the optimal power band for all typical road speeds. Operating such transmissions often uses the same pattern of shifter movement with a single or multiple switches to engage the next sequence of gears. Many of the first automobiles were rear-engined, with a simple belt-drive functioning as a single-speed transmission. The 1891 Panhard et Levassor is considered a significant advance in automotive transmissions since it used

9906-399: The fifth selector on the main shaft. This means that when the vehicle is stopped and idling in neutral with the clutch engaged and the input shaft spinning, the third-, fourth-, and fifth-gear pairs do not rotate. When neutral is selected, none of the gears on the output shaft are locked to the shaft, allowing the input and output shafts to rotate independently. For reverse gear, an idler gear

10033-457: The final laps to win his second Daytona 500. Yarborough was running at the finish in all 30 NASCAR Winston Cup races as he dominated the 1977 season to wrap up his second consecutive title. Yarborough won nine races in 30 starts in his No. 11 Chevelle and finished 386 points ahead of runner-up Richard Petty. Third generation Chevelle NASCAR Winston Cup victories: Date Track Race Winner Car Speed (73-77 seasons) 5 mph bumper A bumper

10160-420: The first contact is with the glass windshield of the passenger compartment. Underride collisions , in which a smaller vehicle such as a passenger sedan slides under a larger vehicle such as a tractor-trailer often result in severe injuries or fatalities. The platform bed of a typical tractor-trailer is at the head height of seated adults in a typical passenger car and thus can cause severe head trauma in even

10287-500: The first two of three consecutive Winston Cup championships. Considered a limited edition "aero" model by NASCAR, the Laguna S-3 was made ineligible for competition following the 1977 season. The Laguna was so fast that NASCAR required the cars be fitted with 'restrictor plates' to effectively slow them down when no other cars had this requirement. Motor Trend said in 1973: "While neither Chevrolet or Pontiac are back in racing,

10414-526: The first-gen Fiat Ducato . Many European cars had manual column shifts and the Renault 16TX had a 5 speed. Column shifters are mechanically similar to floor shifters, although shifting occurs in a vertical plane instead of a horizontal one. Because the shifter is further away from the transmission, and the movements at the shifter and at the transmission are in different planes, column shifters require more complicated linkage than floor shifters. Advantages of

10541-442: The forces required or provide a faster shift time . The first car to use a manual transmission with synchromesh was the 1929 Cadillac . Most North American marques had adopted synchronized manual transmissions, usually for second and high gears, by the mid-1930s. In 1947, Porsche patented the split ring synchromesh system. The 1952 Porsche 356 was the first car to use a transmission with synchromesh on all forward gears. In

10668-401: The forward gears. These devices automatically match the speed of the input shaft with that of the gear being selected, thus removing the need for the driver to use techniques such as double-clutching . The synchromesh transmission was invented in 1919 by Earl Avery Thompson and first used on production cars by Cadillac in 1928. The need for synchromesh in a constant-mesh transmission is that

10795-465: The front end to be flat and free of gaps in this day of jutting bumpers; its block-cut fenders are chauvinistically masculine and no sheet metal is wasted cloaking its tires from view...so the Laguna looks like it could bowl over most of the cars on the road. For 1974, the Laguna was renamed "Laguna Type S-3" and was offered only as the Colonnade coupe. It retained the urethane front end from 1973 with

10922-418: The front-wheel-drive transaxle's ring gear. This allows for a narrower transmission since the length of each countershaft is halved compared with one that contains four gears and two shifters. The fixed and free gears can be mounted on either the input or output shaft or both. For example, a five-speed transmission might have the first-to-second selectors on the countershaft, but the third-to-fourth selector and

11049-437: The gear shift in comparison to the column shifter makes console shifters easier to operate than column shifters. In the 1950s, 1960s, and 1970s, fuel-efficient highway cruising with low engine speed was in some cases enabled on vehicles equipped with 3- or 4-speed transmissions by means of a separate overdrive unit in or behind the rear housing of the transmission. This was actuated either manually while in high gear by throwing

11176-410: The gearshift lever into reverse results in gears moving to mesh together. Another unique aspect of the reverse gear is that it consists of two gears—an idler gear on the countershaft and another gear on the output shaft—and both of these are directly fixed to the shaft (i.e. they are always rotating at the same speed as the shaft). These gears are usually spur gears with straight-cut teeth which—unlike

11303-624: The height mismatch. This mismatch can result in vehicles being so severely damaged that they are inoperable after low-speed collisions. In most jurisdictions, bumpers are legally required on all vehicles. Regulations for automobile bumpers have been implemented for two reasons – to allow the car to sustain a low-speed impact without damage to the vehicle's safety systems, and to protect pedestrians from injury. These requirements conflict: bumpers that withstand impact well and minimize repair costs tend to injure pedestrians more, while pedestrian-friendly bumpers tend to have higher repair costs. Although

11430-410: The helical teeth used for forward gear—results in a whining sound as the vehicle moves in reverse. When reverse gear is selected, the idler gear is physically moved to mesh with the corresponding gears on the input and output shafts. To avoid grinding as the gears begin to the mesh, they need to be stationary. Since the input shaft is often still spinning due to momentum (even after the car has stopped),

11557-419: The increasingly popular unleaded gasoline. A three-speed manual transmission was standard; four-speed manual and Turbo Hydra-Matic three-speed automatic were optional. Crossflow radiators and coolant reservoirs that prevented air from entering the system prevented overheating. Speed and Supercar magazine said in a June 1973 "Street Test": "Chevy gets it right on." "Enough is plenty, that's how we feel about

11684-645: The late 1930s and became common during the 1940s and 1950s. If a U.S. vehicle was equipped with overdrive , it was very likely to be a Borg-Warner type, operated by briefly backing off the accelerator pedal when above 28 mph (45 km/h) to enable, and momentarily flooring the same pedal to return to normal gear. The control simply disables overdrive for such situations as parking on a hill or preventing unwanted shifting into overdrive. [REDACTED] Later, European and Japanese models began to have 4-speed column shifters with this shift pattern: [REDACTED] A majority of North American-spec vehicles sold in

11811-399: The latter usually reserved for high-performance transmissions due to their high cost). Mechanical wear of the synchronizer rings and sleeves can cause the synchromesh system to become ineffective over time. These rings and sleeves have to overcome the momentum of the entire input shaft and clutch disk during each gearshift (and also the momentum and power of the engine, if the driver attempts

11938-457: The lead three laps from the finish and wins the Daytona 500 when leader David Pearson spins on the backstretch. Parsons Chevelle comes from the 32nd starting position to claim the upset win and the biggest victory of his career. May 10, 1975: Music City USA 420 - Darrell Waltrip racks up his first career NASCAR Winston Cup Grand National victory in his No. 17 Laguna with a two-lap triumph in

12065-459: The mechanical linkage for the clutch pedal is replaced by an actuator , servo , or solenoid and sensors , which operate the clutch system automatically when the driver touches or moves the gearshift . This removes the need for a physical clutch pedal. A manual transmission requires the driver to operate the gear stick and clutch in order to change gears (unlike an automatic transmission or semi-automatic transmission , where one (typically

12192-452: The mid-1910s, but consisted of a strip of steel across the front and back. Often treated as an optional accessory, bumpers became more and more common in the 1920s as automobile designers made them more complex and substantial. Over the next decades, chrome-plated bumpers became heavy, elaborative, and increasingly decorative until the late 1950s when U.S. automakers began establishing new bumper trends and brand-specific designs. The 1960s saw

12319-560: The most extensive redesign in their 10-year history. The chassis were as new as the bodies. Wheelbase dimensions were carried over from the second-generation 1968-1972 models, with a sporty 112 inches for coupes and 116 inches for sedans and station wagons on an all-new sturdier perimeter frame with increased front and rear suspension travel, larger, 8½ inch, rear axle, wider, six-inch, wheel rims, refined rear control arm bushings and new shock absorber locations, new body mounts and improved front suspension geometry. The left wheel

12446-531: The new crop intermediates out of GM's styling studios are curiously aerodynamic . They are also curiously competing on the NASCAR circuit tracks, and selling as fast as they can be hauled to the dealerships." Third generation Chevelle NASCAR Winston Cup highlights: March 25, 1973: Southeastern 500-Cale Yarborough, back in NASCAR's fold after a two-year exile in USAC Indy Cars, drives Junior Johnson 's No. 11 Chevrolet Chevelle to an overwhelming victory in

12573-462: The nickname "crash" because the difficulty in changing gears can lead to gear shifts accompanied by crashing/crunching noises. Vehicles with manual transmissions use a clutch to manage the linkage between the engine and the transmission, and decouple the transmission from the engine during gearshifts and when the vehicle is stationary. Without a clutch, the engine would stall any time the vehicle stopped, and changing gears would be difficult (deselecting

12700-406: The other shaft, with a bearing located between the two shafts. In a transmission for transverse engined vehicles (e.g., front-wheel-drive cars), there are usually only two shafts: input and countershaft (sometimes called input and output). The input shaft runs the whole length of the gearbox, and there is no separate input pinion. These transmissions also have an integral differential unit, which

12827-489: The output shaft gears are able to rotate independently of the output shaft itself (through the use of bearings located between the gears and the shaft). Through the use of collars (operated using the shift rods ), the speed of the output shaft becomes temporarily locked to the speed of the selected gear. Some transmission designs—such as in the Volvo 850 and S70—have two countershafts, both driving an output pinion meshing with

12954-424: The output shaft. When the driver selects a gear, the dog clutch for that gear is engaged (via the gear selector rods), locking the transmission's output shaft to a particular gear set. This means the output shaft rotates at the same speed as the selected gear, thus determining the gear ratio of the transmission. The dog clutch is a sliding selector mechanism that sits around the output shaft. It has teeth to fit into

13081-482: The personal-luxury Monte Carlo ; Malibu models made do with a more conventional dashboard and a linear-readout speedometer. The standard engine was a new 140-horsepower 305 two-barrel V8. Optional engines included the 145-horsepower 350 two-barrel V8 and 175-horsepower 400 four-barrel V8. Aero styling had helped make the Laguna popular with NASCAR drivers. The Laguna S3 was outsold by the Malibu Classic coupe and

13208-433: The pitch of each vehicle, so bumpers can bypass each other when the vehicles collide. Preventing override and underride can be accomplished by extremely tall bumper surfaces. Active suspension is another solution to keeping the vehicle level. Bumper height from the roadway surface is essential in engaging other protective systems. Airbag deployment sensors typically do not trigger until contact with an obstruction, and it

13335-616: The requirements of Federal Motor Vehicle Safety Standard Number 215 (FMVSS 215, "Exterior Protection of Vehicles") and promulgated in March 1976. This new bumper standard was placed in the United States Code of Federal Regulations at 49 CFR 581, separate from the Federal Motor Vehicle Safety Standards at 49CFR571. The new requirements, applicable to 1979- model year passenger cars, were called

13462-563: The results, including repair costs. Car makers that do well in these tests tend to publicize the results. In 1990, the IIHS conducted four crash tests on three different-year examples of the Plymouth Horizon . The results illustrate the effect of the changes to the U.S. bumper regulations (repair costs are quoted in 1990 United States dollars ): Today's bumpers are designed to mitigate injuries to pedestrians and minimize weight at

13589-413: The road. The U.S. trucking industry has been slow to upgrade this safety feature, and there are no requirements to repair ICC bars damaged in service. However, in 1996 NHTSA upgraded the requirements for the rear underride prevention structure on truck trailers, and Transport Canada went further with an even more stringent requirement for energy-absorbing rear underride guards. In July 2015, NHTSA issued

13716-401: The same axis, since this reduces the torsional forces to which the transmission casing must withstand. The assembly consisting of both the input and output shafts is referred to as the main shaft (although sometimes this term refers to just the input shaft or output shaft). Independent rotation of the input and output shafts is made possible by one shaft being located inside the hollow bore of

13843-441: The same speed when engaged; otherwise, the teeth would refuse to mesh. This was difficult to achieve, so gear changes were often accompanied by grinding or crunching sounds, resulting in the gearboxes being nicknamed "crash boxes". Even after passenger cars had switched to synchronous transmissions (i.e. with synchronizers), many transmissions for heavy trucks, motorcycles and racing cars remained non-synchronous, in order to withstand

13970-422: The selector forks within the transmission. Motorcycles typically employ sequential manual transmissions , although the shift pattern is modified slightly for safety reasons. Gear selection is usually via the left-foot (or, on older motorcycles; right-foot) shift lever with a layout of 1–N–2–3–4–5–6. During the period when U.S. vehicles usually had only three forward speeds, the most common gear-shifter location

14097-536: The stronger the structure, including the bumpers, the safer the car. A later analysis led to the understanding of crumple zones , rather than rigid construction that proved deadly to passengers because the force from impact went straight inside the vehicle and onto the passenger. NHTSA amended the bumper standard in May 1982, halving the front and rear crash test speeds for 1983 and newer car bumpers from 5 miles per hour (8 km/h) to 2.5 miles per hour (4 km/h), and

14224-714: The threat of death and serious injury to pedestrians in urban environments, because the bull bar is rigid and transmits all force of a collision to the pedestrian, unlike a bumper, which absorbs some force and crumples. In the European Union , the sale of rigid metal bull bars that do not comply with the relevant pedestrian-protection safety standards has been banned. Off-road vehicles often utilize aftermarket off-road bumpers made of heavy gauge metal to improve clearance (height above terrain), maximize departure angles, clear larger tires, and ensure additional protection. Similar or identical to bull bars, off-road bumpers feature

14351-484: The transmission. FF (front-engined, front-wheel drive) vehicles, RR (rear-engined, rear-wheel drive) vehicles and front-engined vehicles with rear-mounted gearboxes often require a mechanical linkage to connect the shifter to the transmission. Some vehicles have a gear lever mounted on the steering column. A 3-speed column shifter, which came to be popularly known as a "three on the tree", began appearing in America in

14478-437: The use of bumper covers made of flexible materials. Front bumpers, especially, have been lowered and made of softer materials, such as foams and crushable plastics, to reduce the severity of impact on legs. For passenger cars, the height and placement of bumpers are legally specified under both U.S. and EU regulations. Bumpers do not protect against moderate-speed collisions, because during emergency braking, suspension changes

14605-415: The use of lighter chrome-plated blade-like bumpers with a painted metal valance filling the space below it. Multi-piece construction became the norm as automakers incorporated grilles , lighting , and even rear exhaust into the bumpers. On the 1968 Pontiac GTO , General Motors incorporated an "Endura" body-colored plastic front bumper designed to absorb low-speed impact without permanent deformation. It

14732-505: The vehicle is subjected to barrier crash tests at 5 miles per hour (8 km/h) for front and 2.5 mph (4 km/h) for rear bumper systems. The requirements effectively eliminated automobile bumper designs that featured integral automotive lighting components such as tail lamps. In October 1972, the U.S. Congress enacted the Motor Vehicle Information and Cost Saving Act (MVICS), which required NHTSA to issue

14859-467: The vehicle's transmission in much the same way a floor-mounted shifter can. However, because of the location of the gear shifter in comparison to the locations of the column shifter and the floor shifter, as well as the positioning of the shifter to the rest of the controls on the panel often require that the gearshift be mounted in a space that does not feature a lot of controls integral to the vehicle's operation, or frequently used controls, such as those for

14986-620: The weakened bumper standard. They argued that the 1982 standard increased overall consumer costs without any attendant benefits except for automakers. In 1986, Consumers Union petitioned NHTSA to return to the Phase II standard and disclose bumper strength information to consumers. In 1990, NHTSA rejected that petition. In the United States, the Insurance Institute for Highway Safety (IIHS) subjects vehicles to low-speed barrier tests (6 mph or 9.7 km/h) and publishes

15113-490: The years. Bumpers ideally minimize height mismatches between vehicles and protect pedestrians from injury . Regulatory measures have been enacted to reduce vehicle repair costs and, more recently, impact on pedestrians. Bumpers were, at first, just rigid metal bars. George Albert Lyon invented the earliest car bumper. The first bumper appeared on a vehicle in 1897, and Nesselsdorfer Wagenbau-Fabriksgesellschaft, an Austrian carmaker, installed it. The construction of these bumpers

15240-650: Was adjusted to have slightly more positive camber than the right which resulted in a more uniform and stable steering feel on high-crown road surfaces while maintaining excellent freeway cruising stability. Clearances for spring travel were improved for a smoother ride over all types of surfaces; the coil springs at each wheel were computer-selected to match the individual car's weight. Power brakes with front disc brake calipers were standard on all 1973 Chevelles. Additional new features were an acoustical double-panel roof, tighter-fitting glass, flush-style outside door handles, molded full foam front- and rear-seat construction,

15367-464: Was featured in a TV advertisement with John DeLorean hitting the bumper with a sledgehammer and no damage resulted. Similar elastomeric bumpers were available on the front and rear of the 1970-71 Plymouth Barracuda . In 1971, Renault introduced a plastic bumper ( sheet moulding compound ) on the Renault 5 . Current design practice is for the bumper structure on modern automobiles to consist of

15494-466: Was introduced in the 2012 Porsche 911 (991) . In 2008, 75.2% of vehicles produced in Western Europe were equipped with manual transmission, versus 16.1% with automatic and 8.7% with other. A manual transmission has several shafts with various gears and other components attached to them. Most modern passenger cars use 'constant-mesh' transmissions consisting of three shafts: an input shaft ,

15621-461: Was on the steering column, a layout that was sometimes called "three on the tree". By contrast, high-performance cars, and European vehicles in general, mostly used a four-speed transmission with floor-mounted shifters. That layout was referred to as "four on the floor". Most FR (front-engined, rear-wheel drive) vehicles have a transmission that sits between the driver and the front passenger seat. Floor-mounted shifters are often connected directly to

15748-441: Was seen as beneficial to occupant safety among automotive engineers . Modern theories of vehicle crashworthiness point in the opposite direction, towards vehicles that crumple progressively . A completely rigid vehicle might have excellent bumper protection for vehicle components, but would offer poor occupant safety . Bumpers are increasingly being designed to mitigate injury to pedestrians struck by cars, such as through

15875-474: Was standard with a four-speed manual available only with the 454 engine. Horsepower was seemingly lower due to the way it was calculated as 'net' starting in 1972 as opposed to 'gross' horsepower ratings of 1971 and prior years. The 1975 Laguna S-3 was introduced mid-year in January 1975. This time, it had a slanted, urethane-covered aero-style nose designed for NASCAR (which later resurfaced again in 1983 with

16002-449: Was the only transmission offered as manual transmissions were discontinued. Options included an Econominder gauge package, during the gasoline shortage of the mid-seventies. In its third and final year, the 1976 Laguna Type S-3 again featured a sloped, body-color urethane front end and quarter-window louvers, but with new rear styling and horizontal taillights shared with other Chevelles. Lagunas shared their round-gauge instrument panel with

16129-407: Was unreliable as they featured only a cosmetic function. Early car owners had the front spring hanger bolt replaced with ones long enough to attach a metal bar. G.D. Fisher patented a bumper bracket to simplify the attachment of the accessory. The first bumper designed to absorb impacts appeared in 1901. It was made of rubber, and Frederick Simms gained a patent in 1905. Automakers added bumpers in

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