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Saturday, August 1, 2009

Pontiac GTO History 1964 to 1974

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The Pontiac GTO was a high performance model built by Pontiac from 1964 to 1974 and is often considered the first true muscle car. From 1964 until midway through 1973 it was closely related to the Pontiac Tempest and for the 1974 model year it was based on the Pontiac Ventura.

Birth of the GTO
The GTO was the brainchild of Pontiac engineer Russell Gee, an engine specialist, and Pontiac’s chief engineer John De Lorean. However it was Shane Wiser who was the first to think of the idea of the GTO. The name, which was DeLorean's idea, was inspired by the Ferrari 250 GTO, the highly successful race car – it drew protests from purists who considered it close to sacrilege. Whereas other manufacturers were concentrating on their full-sized lines, Pontiac saw the potential for dropping a big block engine into an intermediate frame and marketing it at a budget price.

In early 1963 General Motors management issued an edict banning divisions from involvement in auto racing. At the time, Pontiac's advertising and marketing approach was heavily based on performance, and racing was an important component of that strategy. Jim Wangers proposed a way to retain the performance image that the division had cultivated with a new focus on street performance. Pontiac sneaked past the GM restriction on this by manufacturing the GTO by transforming the upcoming redesigned Pontiac Tempest to creare the hottest performance machine yet.

The Pontiac Tempest which was set to revert to a conventional front-engine, front transmission, rear-wheel drive configuration into a "Super Tempest" with the larger 389 in³ (6.5 Ltr) Pontiac V8 engine from the full-sized Pontiac Catalina and Bonneville that replaced the standard 326 in³ (5.3 Ltr) Tempest V8. By promoting the big engined Pontiac Tempest as a special high-performance model, they could appeal to the speed-minded youth market which had also been recognized by Ford Motor Company's Lee Iacocca, who was at that time preparing the Ford Mustang.

As mentioned the Pontiac GTO was technically a violation of GM policy of the time, limiting the A-body intermediate line to a maximum engine displacement of 330 in³ (5.4 Ltr). Since the GTO was an option package and not standard equipment, it could be considered to fall into a loophole in the policy. Pontiac General Manager Elliot "Pete" Estes approved the new model, although sales manager Frank Bridge, who did not believe it would find a market, insisted on limiting initial production to no more than 5,000 cars. Had the model been a failure, Estes would have likely had to carry the can, as it turned out, it was a great success. Frank Bridge's sales forecast proved inaccurate: the Pontiac Tempest GTO package had sold 10,000 units before the beginning of the 1964 calendar year, and total sales were 32,450.

Although Pontiac had strenuously promoted the GTO in advertising as the "GTO Tiger," it had become known in the youth market as the "Goat." Pontiac management attempted to make use of the new nickname in advertising but were vetoed by upper management, which was dismayed by its irreverent tone. The Pontiac GTO would stand the automobile industry on end and lead to a host of imitators - it would fuel the competition between GM, Chrysler, and Ford that would keep the muscle car industry thriving for many years to come until its un-befitting death in 1974.

Pontiac GTO 1st Generation (1964 to 1967)

1964 Pontiac GTO
The first Pontiac GTO was an option package for the Pontiac Tempest, available with the two-door sedan, hardtop coupe, and convertible body styles. For a bargain of US $296, it included the 389 in³ V8 (rated at 325 hp (242 kW) at 4800 rpm) with a single Carter AFB four-barrel carburettor and dual exhaust, chromed valve covers and air cleaner, 7 blade clutch fan, a floor-shifted three-speed manual transmission with Hurst shifter, stiffer springs, larger diameter front sway bar, wider wheels with 7.50 x 14 redline tires, hood scoops, and GTO badges. Optional equipment included a four-speed manual transmission, two-speed automatic transmission, a more powerful "Tri-Power" carburation rated at 348 hp (260 kW), metallic drum brake linings, limited slip differential, heavy-duty cooling, ride and handling package, and the usual array of power and convenience accessories. With every available option, the GTO cost about US$ 4,500 and weighed around 3,500 pounds (1,600 kg).

Most contemporary road tests used the more powerful Tri-Power engine and four-speed. Car Life clocked a GTO so equipped at 0-60 miles per hour (0-97 km/h) in 6.6 seconds, through the standing quarter mile in 14.8 seconds with a top speed of 99 miles per hour (158 km/h). Like most testers, they criticized the slow steering, particularly without power steering, and inadequate drum brakes, which were identical to those of the normal Tempest. Car and Driver incited controversy when it printed that a Pontiac GTO that had supposedly been tuned with the "Bobcat” package (see below) was clocked at a quarter mile time of 12.8 seconds and a top speed of 112 mph (179 km/h) on racing slicks. Later reports strongly suggest that the Car and Driver GTO’s were equipped with a 421 in³ (6.9 Ltr) engine that was optional in full-sized Pontiacs. Since the two engines were difficult to distinguish externally, the subterfuge was not immediately obvious.

Throughout the 1960s, Royal Pontiac, a Pontiac car dealer in Royal Oak, Michigan, offered a special tune-up package for Pontiac 389 engines. Many were fitted to GTO’s, and the components and instructions could be purchased by mail as well as installed by the dealer. The name "Bobcat" came from the improvised badges created for the modified cars, combining letters from the "Bonneville" and "Catalina" nameplates. Many of the Pontiacs made available for magazine testing were equipped with the Bobcat kit. The GTO Bobcat accelerated 0-60 in 4.6 seconds.

The precise components of the kit varied but generally included pieces to modify the spark advance of the distributor, limiting spark advance to 34-36° at no more than 3,000 rpm (advancing the timing at high rpm for increased power), a thinner head gasket to raise compression to about 11.23:1, a gasket to block the heat riser of the carburettor (keeping it cooler), larger carburettor jets, high-capacity oil pump, and fibreglass shims with lock nuts to hold the hydraulic valve lifters at their maximum point of adjustment, allowing the engine to rev higher without "floating" the valves. Properly installed, the kit could add between 30 and 50 horsepower (20-40 kW), although it required high-octane super premium gasoline of over 100 octane to avoid spark knock with the higher compression and advanced timing.

Production Numbers:
Hardtop Coupe: 18,422
Sports Coupe: 7,384
Convertible: 6,644

1965 Pontiac GTO
The Pontiac Tempest line, including the GTO, was restyled for the 1965 model year, adding 3.1 inches (79 mm) to the overall length while retaining the same wheelbase and interior dimensions. Front and rear styling were changed with the GTO getting Pontiac's characteristic vertically stacked quad headlights. Overall weight increased about 100 pounds (45 kg). Brake lining area increased nearly 15%. The dashboard design was improved, and an optional rally gauge cluster at US $86 added a more legible tachometer and oil pressure gauge.

The 389 engine had revised cylinder heads with re-cored intake passages, improving breathing. Rated power increased to 335 hp (250 kW) @ 5,000 rpm for the base 4—barrel engine; the Tri-Power was rated 360 hp ((268 kW) @ 5,200 rpm. The Tri-Power engine had slightly less torque than the base engine, 424 [[Foot-pound forceft•lbf]] (574 N•m) @ 3,600 rpm versus 431 ft•lbf (584 N•m) @ 3,200 rpm. Transmission and axle ratio choices remained the same.

The restyled Pontiac GTO had a new simulated hood scoop. A rare, dealer-installed option was a metal underhood pan and gaskets that allowed the scoop to be opened, transforming a cosmetic device into a functional cold air intake. The scoop was low enough that its effectiveness was questionable (it was unlikely to pick up anything but boundary layer air), but it at least admitted cooler, denser air, and allowed more of the engine's formidable roar to escape.

“Car Life” tested a 1965 GTO with Tri-Power and what they considered the most desirable options (close-ratio four-speed manual transmission, power steering, metallic brakes, rally wheels, 4.11 limited-slip differential, and Rally Gauge Cluster), with a total sticker price of US $3,643. With two testers and equipment aboard, they recorded 0-60 miles per hour (0-97 km/h) in 5.8 seconds, the standing quarter mile in 14.5 seconds with a trap speed of 100 miles per hour (160 km/h), and an observed top speed of 114 miles per hour (182.4 km/h) at the engine's 6,000 rpm redline. Even Motor Trend's four-barrel test car, a heavier convertible handicapped by the two-speed automatic transmission and the lack of a limited slip differential, ran 0-60 mph in 7 seconds and through the quarter mile in 16.1 seconds at 89 miles per hour (142.4 km/h).

Major criticisms of the Pontiac GTO continued to center on its slow steering (ratio of 17.5:1, four turns lock-to-lock) and mediocre brakes. “Car Life” was satisfied with the metallic brakes on its GTO, but “Motor Trend” and “Road Test” found the standard drums with organic linings to be alarmingly inadequate at high-speed driving.

Sales of the GTO, abetted by a formidable marketing and promotional campaign that included various merchandise (and songs!) more than doubled to 75,342 of which 20,547 had the tri-power option. It was already spawning many imitators, both within other GM divisions and its competitors.

Production Numbers:
Hardtop Coupe: 55,722
Convertible: 11,311
Sports Coupe: 8,319

1966 Pontiac GTO
The 1966 Pontiac GTO became a separate model series rather than an optional performance package for the Pontiac Tempest. It was restyled again with gorgeous coke-bottle contours with the roof and taillights receiving the most attention. The kicked-up rear fender lines, and a slightly "tunnelled" backlight helped to give it this more curvaceous styling. The tail light featured a rare louvered cover, only seen on the GTO. Also an automotive industry first, plastic front grilles replaced the pot metal and aluminium versions seen on earlier years. Now available as a pillared sports coupe, a hardtop sans pillars, or a convertible. Overall length grew only fractionally, to 206.4 inches (524 cm), still on a 115 inch (292 cm) wheelbase, while width expanded to 74.4 inches (189 cm). Rear track increased one inch (2.5 cm). Overall weight remained about the same.

The instrument panel was redesigned and more integrated than in previous years with the ignition switch moved from the far left of the dash to the right of the steering wheel. The four pod instruments continued, and the GTO's dash was highlighted by walnut veneer trim. New “Strato” bucket seats were introduced with higher and thinner seat backs and contoured cushions for added comfort and adjustable headrests were introduced as a new option.

Engine choices remained the same as the previous year until mid year when GM banned multi-carb setups for all cars except the Chevrolet Corvette - probably in the face increasing emissions standards. A new rare engine option was offered: the XS engine option consisted of a factory Ram Air set up with a new 744 high lift cam. Approximately 35 factory installed Ram Air packages are believed to have been built, although 300 dealership installed Ram Air packages are estimated to have been ordered. On paper, the package was said to produce the same 360 hp (270 kW) as the non-Ram Air Tri Power car, though these figures are believed to have been grossly underestimated in order to get past GM mandates.

Sales increased to 96,946, the highest production figure for all GTO years and the highest ever for a true muscle car!

Production Numbers:
Hardtop Coupe: 73,785
Convertible: 12,798
Sports Coupe: 10,363

1967 Pontiac GTO
The Pontiac GTO underwent a few styling changes in 1967. The louver-covered tail lights were replaced with eight tail lights, four on each side and the grille was restyled again. Rally II wheels with colored lug nuts were also available on this years model. The GTO emblems located on the rear part of the fenders were moved to the chrome rocker panels. Pontiac GTO sales for 1967 remained high at 81,722.

The GTO also saw several mechanical changes in 1967. Undaunted by the death of their tri-power setup, Pontiac unveiled an all new 400 cid enlargement of the 389 cid engine. The Tri-Power carburetion system was replaced with a Rochester Quadrajet four-barrel carburettor. The new 400 cid engine was available in economy @ 255bhp (utilizing a two-barrel carburetor), standard @ 335bhp, High Output (HO) @ 360bhp and Ram Air @ 360bhp versions. The tiger could still roar.

The two-speed automatic transmission was also replaced with a three-speed Turbo-Hydramatic TH-400. The TH-400 was equipped with a Hurst Performance Dual-Gate shifter, called a "his/hers" shifter, that permitted either automatic shifting in "Drive" or manual selection through the gears. Front disc brakes were also an option in 1967. Emission controls were fitted in the GTO’s sold in California.

Production Numbers:
Hardtop Coupe: 65,176
Convertible: 9,517
Sports Coupe: 7,029

Pontiac GTO 2nd Generation (1968 to 1974)

1968 Pontiac GTO
The Pontiac GTO was drastically restyled for 1968 and gained GM's new split wheelbase A-body. GM redesigned its A-body line with a more curvaceous, "fastback" styling. The previous 115 inch (292 cm) wheelbase was shortened to 112 inches (2,800 mm) (284 cm) for all two-door models. Overall length was reduced 5.9 inches (150 mm) and height dropped half an inch (12 mm), but overall weight was up about 75 pounds (34 kg) on the 1967 model.

Pontiac abandoned the familiar stacked headlights for hidden headlights behind the split grille. This was actually a US $52 option but were seen on so many GTO’s people thought they were standard. The signature hood scoop was replaced by dual scoops on either side of a prominent hood bulge extending rearward from the protruding nose.

A unique feature was the new body-coloured Endura front bumper, which was a rubber bumper that gave the car a bumper-less appearance. It was designed to absorb impact without permanent deformation at low speeds. Pontiac touted this feature heavily in its advertising, most famously in a commercial with John DeLorean bashing a GTO's bumper with a sledgehammer to no dsicerible effect. Though a rare option, a GTO could be ordered with "Endura Delete", in which the Endura bumper would be replaced by a chrome front bumper and grille from the Pontiac Le Mans.

A carry-over from 1967 was the 4-piston calliper disc brake option. While most 1968 models had drum brakes all around, this rare option provided greater stopping power and could be found on other GM A-Body vehicles of the same period. Another popular option, actually introduced during the 1967 model year, was a hood-mounted tachometer, located in front of the windshield and lighted for visibility at night. An in-dash tachometer was also available, but the hood tachometer became something of a status symbol. Another feature was concealed windshield wipers, hidden below the rear edge of the hood. They presented a cleaner appearance and were another Pontiac first for the industry. 1968 was also the last year the GTO’s offered separate vent or "wing" windows and was the only year for crank-operated vent windows.

Redline bias-ply tires continued as standard equipment on the 1968 GTO, though they could be replaced by whitewall tires at no extra cost. A new option was radial tires for improved ride and handling. However, very few were delivered with the radial tires because of manufacturing problems encountered by supplier B.F. Goodrich. The radial tire option was discontinued after 1968. Pontiac did not offer radial tires as a factory option on the GTO again until the 1974 model.

Powertrain options remained substantially the same as in 1967, but the standard GTO engine's horsepower rating rose to 350 hp (261 kW) @ 5,000 rpm. All engines were tuned for more torque at lower rpm’s. At mid-year, a new Ram Air package, known as Ram Air II, became available. It included freer breathing cylinder heads, round port exhaust and the 041 cam. Official horsepower rating was not changed, although actual output was likely much higher.

Hot Rod tested a four-speed standard GTO and obtained a quarter mile reading of 14.7 seconds at 97 mph (156 km/h) in pure stock form. Motor Trend clocked a four-speed Ram Air with 4.33 rear differential at 14.45 seconds @ 98.2 mph (158.0 km/h) (158.0 km/h) and a standard GTO with Turbo-Hydramatic and 3.23 gears at 15.93 seconds @ 88.3 mph (142.1 km/h). Testers were split about handling, with Hot Rod calling it "the best-balanced car [Pontiac] ever built," but Car Life chiding its excessive nose heaviness, under steer, and inadequate damping.

Now facing serious competition both within GM and from Ford, Dodge, and Plymouth (particularly the low-cost Plymouth Road Runner) the Pontiac GTO won Motor Trend's Car of the Year award, and sales remained strong at 87,684 which would ultimately prove to be the second-best sales year for the GTO.

Production Numbers:
Hardtop Coupe: 77,704
Convertible: 9,980

1969 Pontiac GTO
The 1969 Pontiac GTO did not have the vent windows, had a slight grille and taillight revision, moved the ignition key from the dashboard to the steering column, and the gauge faces changed from steel blue to black. In addition, the rear quarter-panel mounted side marker lamps changed from a red lens shaped like the Pontiac "V" crest to one shaped like the broad GTO badge. However the big news for 1969 was the introduction of a new option for the GTO called the “The Judge”!

The previous economy engine and standard 350 hp 400 in³ V8 remained, while the 360 hp (270 kW) HO engine was in its last year. The 400 in³ Ram Air III was rated at 366 hp (273 kW) @ 5,100 rpm, while the top option was the 370 hp (276 kW) Ram Air IV, which featured special header-like high-flow exhaust manifolds, high-flow cylinder heads, a specific high-rise aluminium intake manifold, larger Rochester QuadraJet four-barrel carburetor, high-lift/long-duration camshaft, plus various internal components capable of withstanding higher engine speeds and power output. Unlike the big-block Chevy and Hemi motors, the Ram Air IV utilized hydraulic lifters. As a result, it did not overheat in traffic, nor did it foul spark plugs, which set it apart from the large-displacement performance engines seen in other muscle cars.

By this time, the gross power ratings of both Ram Air engines were highly suspect, bearing less relationship to developed horsepower and more to an internal GM policy limiting all cars except the Corvette to no more than one advertised horsepower per ten pounds of curb weight. The higher-revving Ram Air IV's advertised power peak was actually listed at 5,000 rpm—100 rpm lower than the less-powerful Ram Air III. The Ram Air V was introduced in 1969. It was a special 400 block with newly designed high compression tunnel port heads and a special high rise intake manifold. A prototype GTO so equipped could go 0-60 mph in 5.2 seconds, and the quarter-mile time was 11.5 seconds at 123 mph (198 km/h). Ram Air Vs were not installed in GTOs at the factory; it was available only as an "over-the-counter" product, and most went to Pontiac racers of the time.

The significant event of 1969 was the introduction of a new option for the Pontiac GTO called “The Judge”. Rumoured to be a sleeper budget model to combat the Plymouth Road Runner, it actually was the opposite. The Judge name came from a comedy routine, "Here Comes the Judge", used repeatedly on the "Rowan & Martin's Laugh-In TV" show. Advertisements used slogans like "All rise for The Judge" and "The Judge can be bought." As originally conceived, the Judge was to be a low-cost GTO, stripped of some gimmicks to make it competitive with the Plymouth Road Runner. During its development, however, it was decided to make it the ultimate in street performance and image. The resulting package ended up being US $337 more expensive than a standard GTO, and included the 366bhp Ram Air III 400 cid V8, styled wheels, Hurst shifter (with a unique T-shaped handle), wider tires, various decals, and a rear spoiler. Pontiac claimed that the spoiler had some functional effect at higher speeds, producing a small but measurable down force, but it was of little value at legal speeds except for style. The Judge was initially offered only in "Carousel Red," but late in the model year a variety of other outrageous colors became available.

The Pontiac GTO was surpassed in sales both by the Chevrolet Chevelle SS396 and the Road Runner, but 72,287 were sold during the 1969 model year, with 6,833 of them being The Judge.

Production Numbers:
Hardtop Coupe: 58,126
Convertible: 7,328
Judge Hardtop Coupe: 6,725
Judge Convertible: 108

1970 Pontiac GTO
The Pontiac GTO was radically restyled for 1970 and received a new front end, body creases, and a redesigned rear end. Hidden headlights were deleted in favor of four exposed round headlamps outboard of narrower grille openings. The nose retained the protruding vertical prow theme, although it was less prominent. While the standard Tempest and LeMans had chrome grilles, the GTO retained the Endura urethane cover around the headlamps and grille. The GTO had evolved into more of a luxo-cruiser than all-out muscle car, as was the market trend at the time.

The suspension was upgraded with the addition of a rear anti-roll bar, essentially the same bar as used on the Oldsmobile 442 and Buick Gran Sport. The front anti-roll bar was slightly stiffer. The result was a useful reduction in body lean in turns and a modest reduction of understeer. Another handling-related improvement was optional variable-ratio power steering. Turning diameter was reduced from 40.9 feet (12.5 m) to 37.4 feet (11.4 m).

The base engine was unchanged for 1970, however the low-compression economy engine was dropped but the Ram Air III and Ram Air IV remained available, although the latter was now a special-order option. A new option was Pontiac's 455 engine available now that GM had rescinded its earlier ban on intermediates with engines larger than 400 (though it was not available until the end of the 1970 season on the Judge). The 455, a long-stroke engine taken from the full-size Pontiac Bonneville line, was only moderately stronger than the base 400 and actually less powerful than the Ram Air III.

A new and short-lived option on the 1970 GTO was the Vacuum Operated Exhaust (VOE - Option Code W-73). The VOE option was an attempt to simplify the old hot rod trick of opening up the exhaust system for more power. With the VOE option, the driver could pull on a knob under the dash marked ‘EXHAUST’ and the engine vacuum was routed to a diaphragm on each muffler. The diaphragm opened an internal baffle and gave the exhaust an express route through the muffler. The device reduced backpressure (and thus increased power), but it also significantly increased the noise level caused by the exhaust. This option was available only from early November 1969 through January 1970. Pontiac management were ordered to cancel the VOE option by GM's upper management following a TV commercial for the GTO that aired during Super Bowl IV on CBS January 11, 1970. In that commercial, entitled "The Humbler," which was broadcast only that one time, a young man pulled up in a new GTO to a drive-in restaurant with dramatic music and exhaust noise in the background, pulling the "EXHAUST" knob to activate the VOE and then left the drive-in to do some street racing. Top GM executives saw the commercial, and immediately cancelled the option, due to the Federal government's increasing restrictions on emissions and noise levels. Only 233 GTO's were built with the VOE option in that short time, which was priced at just $63.19.

The Judge remained available as an option on GTOs. The Judge came standard with the Ram Air III, while the Ram Air IV was optional. Though the 455 in³ was available as an option on the standard GTO throughout the entire model year, the 455 was not offered on The Judge until late in the year. "Orbit Orange" became the new standard color for the '70 Judge, but any GTO color was available. Striping was relocated to the upper wheel well brows. An Orbit Orange 1970 GTO Judge with the 455 engine and Turbo Hydra-Matic transmission was one of the featured cars in the movie Two-Lane Blacktop, which depicted a cross-country race between the new GTO and a 1955 Chevrolet Bel Air.

The new styling did little to help declining sales, which were now being hit by sagging buyer interest in all muscle cars and by the punitive surcharges levied by automobile insurance companies, which sometimes resulted in insurance payments higher than car payments for some drivers. Sales were down to 40,149, of which 3,797 were The Judge - of those 3,797 Judges built, only 168 were ordered in convertible form. The Pontiac GTO remained the third best-selling intermediate muscle car outsold only by the Chevrolet Chevelle SS 396/454 and Plymouth Road Runner.

Production Numbers:
Hardtop Coupe: 32,737
Convertible: 3,615
Judge Hardtop Coupe: 3,629
Judge Convertible: 168

1971 Pontiac GTO
The 1971 Pontiac GTO had another facelift albeit modest. The front end was restyled this time with wire-mesh grilles, horizontal bumper bars on either side of the grille opening, more closely spaced headlamps, and a new hood with the dual scoops relocated to the leading edge, not far above the grille. Overall length grew slightly to 203.3 inches (516 cm).

GM announced that all engines would have to run on unleaded gas to meet new government regulations and compression ratios and power ratings plummeted.
The Ram Air engines did not return for 1971. The standard GTO engine was still the 400 in³ V8, but now with 8.2:1 compression. Power was rated at 300 hp (223 kW). The top GTO engine for 1971 was the new 455 in³ HO V8 with four-barrel carburetor, 8.4 to 1 compression ratio and 325 hp (242 kW), only available with the automatic transmission.
Pontiac tried to compensate for the drop in engine power by adjusting the axle ratio and carburetor but to no avail. Motor Trend tested a 1971 GTO with the 455, four-speed transmission, and 3.90 axle, and obtained a 0-60 mph time of 6.1 seconds and a quarter mile acceleration of 13.4 seconds at 102 mph (164 km/h).

The Judge returned for a final year, now with the 455 HO as standard equipment. Only 374 were sold before The Judge was discontinued in February 1971, including only 17 convertibles - today the rarest of all GTO’s. The Pontiac GTO was also in its last year as its own separate model. In 1971 GTO sales which had been declining since the late sixties crashed. Performance and sales were on the decline and nothing could hide the facts - only 10,532 GTOs were sold.

Production Numbers:
Hardtop Coupe: 9,497
Convertible: 661
Judge Hardtop Coupe: 357
Judge Convertible: 17

1972 Pontiac GTO
In 1972, the Pontiac GTO reverted from a separate model line to a US $353 option package for the LeMans and LeMans Sport coupes. On the base LeMans line, the GTO package could be had with either the low-priced pillared coupe or hardtop coupe. Both models came standard with cloth and vinyl or all-vinyl bench seats and rubber floor mats on the pillared coupe or carpeting on the hardtop, creating a lower-priced GTO. The LeMans Sport, offered only as a hardtop coupe, came with ‘Strato’ bucket seats upholstered in vinyl, along with carpeting on floor and lower door panels, vinyl door-pull straps, custom pedal trim and cushioned steering wheel, much like GTOs of previous years. Other optional equipment was similar to 1971 and earlier models. Planned for 1972 as a GTO option was the ducktail rear spoiler from the Pontiac Firebird, but after a few cars were built with this option, it was cancelled. Rally II and honeycomb wheels were optional on all GTO’s, with the honeycombs now featuring red Pontiac arrowhead emblems on the center caps, while the Rally IIs continued with the same caps as before, with the letters "PMD" (for Pontiac Motor Division).

The Judge was discontinued along with the convertible models - although one GTO convertible is rumoured to have been built, along with three GTO station wagons!
Although Pontiac did not offer a production GTO convertible in 1972, a buyer could order a LeMans Sport convertible with either of the three GTO engines and other sporty/performance options to create a GTO in all but name. Even the GTO's Endura bumper was offered as an option on LeMans/Sport models, with "PONTIAC" spelled out on the driver's side grille rather than GTO.

There was relatively little change in the engines from 1971, however there was a noticeable change in the engine power ratings which dropped dramatically. This difference reflected the industry switch from an engine's gross output (power with no accessories) to its SAE Net output (power with accessories attached). This was supposed to be more representative of the actually power delivered to the wheels. This didn't really ease the pain for performance seekers. The 400 V8 was now rated at 250 bhp (net) while the 455 was available in either 250 or 300 bhp versions.

A very rare option was the 455 HO engine, essentially similar to that used in the Trans Am. It was rated at 300 hp (224 kW) @ 4,000 rpm and 415 ft•lbf (562 N-m) @ 3,200 rpm, also in the new SAE net figures. Despite its modest 8.4:1 compression, it was as strong as many earlier engines with higher gross power ratings; yet like all other 1972-model engines, it could perform on low-octane regular leaded, low-lead or unleaded gasolines. Only 646 cars with this engine were sold.

Sales plummeted by 45%, to 5,811. Some sources discount the single convertible and the three anomalous wagons, listing the total as 5,807.

Production Numbers:
Hardtop Coupe: 5,811

1973 Pontiac GTO
This year saw the end of the once great Pontiac GTO. Once again an option package for the LeMans, the 1973 GTO shared the reskinned A-body with its "Colonnade" hardtop styling. This eliminated true hardtop design because of the addition of a roof pillar but retention of the frameless door work. The hood and tail took on displeasing triangular shapes and the rear side windows were now of a fixed design that could not be opened and also in a triangular shape.

Again, the 1973 GTO option was offered on two models including the base LeMans coupe or the LeMans Sport Coupe. The base LeMans coupe featured a cloth-and-vinyl or all-vinyl bench seat while the more lavish LeMans Sport Coupe had all-vinyl interiors with ‘Strato’ bucket seats or a notchback bench seat with folding armrest. The LeMans Sport Coupe also had louvered rear side windows from the Grand Am in place of the standard triangular windows of the base LeMans. This would be the last year the GTO would be based on the LeMans models.

New federal laws for 1973 demanded front bumpers capable of withstanding 5 mile per hour (8 km/h) impacts with no damage to the body (5 mph rear bumpers became standard in 1974). The result was the use of prominent and heavy chrome bumpers front and rear. The overall styling of the 1973 Pontiac A-body intermediates (LeMans, Luxury LeMans, GTO and Grand Am) was generally not well received by the car buying public.

In contrast, the Pontiac Grand Prix and Chevrolet Monte Carlo, which were also derived from the intermediate A-body, were much better received because of their squared-off styling and formal rooflines with vertical windows. Pontiac's sister division, Oldsmobile, received better reviews from the automotive press and the car-buying public with the similar-bodied Cutlass.

The standard 400 in³ V8 in the 1973 GTO was further reduced in compression to 8.0:1, dropping it to 230 hp (170 kW). The 400 engine was available with any of the three transmissions including the standard three-speed manual, or optional four-speed or Turbo Hydra-Matic. The 455 in³ V8 remained optional but was dropped to 250 hp (186 kW) and available only with the Turbo Hydra-Matic transmission. The 455 HO engine did not reappear, but GM initially announced the availability of a Super Duty 455 engine (shared with the contemporary Pontiac Trans Am SD455), and several such cars were made available for testing, impressing reviewers with their power and flexibility. Nevertheless, the Super Duty was never actually offered for public sale in the GTO. Also, eight 455SD Grand Ams were also built for testing, and eventually all were destroyed as well.

Sales dropped to 4,806, thanks in part to competition from the new Grand Am and the lack of promotion for the GTO. By the end of the model year an emerging energy crisis quashed consumer interest in muscle cars.

Production Numbers:
Hardtop Coupe: 4,806

1974 Pontiac GTO
Wanting to avoid internal competition with the "Euro-styled" Pontiac Grand Am, and looking for an entry into the compact muscle market populated by the Plymouth Duster 360, Ford Maverick Grabber and AMC Hornet X, Pontiac moved the 1974 GTO option to the compact Pontiac Ventura. The Ventura shared its basic body shell and sheetmetal with the Chevrolet Nova - critics dubbed it "a Chevy Nova in drag”. The once proud GTO was now reduced to an option on the Ventura either as a hatchback or a coupe.

The US$195 GTO package included a three-speed manual transmission with Hurst floor shifter, heavy-duty suspension with front and rear anti-roll bars, “shaker hood” air scoop, special grille, mirrors, and wheels, and various GTO emblems. Bias-belted tires were standard equipment, but a radial tuned suspension option added radial tires along with upgraded suspension tuning for improved ride and handling.

The GTO option was available in both the base Ventura and Ventura Custom lines as either a two-door sedan or hatchback coupe. The base Ventura interior consisted of bench seats and rubber floor mats, while the Ventura Custom had upgraded bench seats or optional ‘Strato’ bucket seats along with carpeting, cushioned steering wheel, and custom pedal trim.

The only engine was the 350 in³ (5.7 Ltr) V8 with 7.6:1 compression and a single four-barrel carburetor. It was rated at 200 hp (149 kW) This marked the first (and only) time the GTO came with any engine smaller than 389 cid. Optional transmissions included a wide-ratio four-speed with Hurst shifter or the three-speed Turbo Hydra-Matic.
Cars Magazine tested a 1974 GTO with the optional four-speed and obtained a 0-60 mph time of 7.7 seconds and a quarter mile reading of 15.72 seconds @ 88 mph (142 km/h).

Sales were an improvement over 1973, at 7,058, but not enough to justify continuing the model. Although it died a painful death, the GTO will always be remembered as the Great One that started it all.

Production Numbers:
2D Coupe: 5,335
2D Hatchback: 1,723

1975 onwards
Pontiac had planned to offer a 1975 GTO, again based on the compact Ventura and powered by a Pontiac built 350 in³ V8. The Ventura and other GM compacts underwent substantial styling and engineering changes, the latter including front and rear suspensions similar to the sporty Firebird. In the end, however, the Pontiac GTO was discontinued following a corporate decision to switch to Buick V8 engines on the 1975 Ventura line, though Pontiac V8s were continued in all other division models.

In 1975, an enterprising Pontiac dealer in the Eastern United States reportedly decided to "create" a new GTO. Sensing that the 1974 GTO should have continued on the intermediate LeMans platform rather than downsized to the Ventura line, this dealer advertised and sold an undetermined number of 1975 Pontiac GTO’s. These cars were factory-ordered by the dealer as LeMans Sport Coupes equipped with the 400 or 455 in³ V8s with four-barrel carburetors, Turbo Hydra-Matic transmissions, ‘Strato’ bucket seats and console, power steering, power disc brakes, Rally II or Honeycomb wheels, and Radial Tuned Suspension with whitewall or white-lettered radial tires. The dealer replaced the Pontiac and LeMans nameplates with "GTO" badges inside and out. This dealer-made 1975 GTO could be ordered with any LeMans exterior/interior combination along with any other extra-cost options available on the regular LeMans.

In 1976, Jim Wangers reportedly presented a LeMans Sport Coupe as a new GTO Judge prototype with a 400 in³ V8 that was painted Carousel Red to Pontiac division officials as a possible GTO revival to supplement dramatic sales increases for the Firebird Trans Am (now accounting for 50% of Firebird sales) for those buyers who wanted a sporty performance car but needed a roomier back seat and larger trunk. However, division officials turned down the idea of an intermediate-sized GTO, but the concept was considered and approved for production; not as a GTO revival, but as the 1977 Pontiac Can Am.

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