Pontiac GTO, 1970
The Pontiac GTO was an automobile built by Pontiac from 1964 to 1974, and by General Motors Holden in Australia from 2003 to 2006. It is often considered the first true muscle car. From 1964 until 1973.5, it was closely related to the Pontiac Tempest, but for its final year it was based on the Pontiac Ventura. The 21st century GTO is essentially a left hand drive Holden Monaro, itself a coupe variant of the Holden Commodore.
Second generation
1968
GM redesigned its A-body line for 1968, with more curvaceous, "bustleback" fastback styling. The previous 115 inch (292 cm) wheelbase was shortened to 112 inches (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). Pontiac abandoned the familiar stacked headlights for hidden headlights behind the split grille (actually a US$52.66 option, but seen on many GTOs). The signature hood scoop was replaced by dual scoops on either side of a prominent hood bulge extending from the protruding nose.
Powertrain options remained substantially the same as in 1967, but the standard GTO engine rose to 350 hp (261 kW) @ 5,000 rpm. At mid-year, a new Ram Air package became available with freer-breathing cylinder heads, round port exhaust and the 744 cam and 3.90:1 rear differential. Horsepower rating was not changed, although actual output was likely somewhat higher, especially with open exhausts. Another carry-over from 1967 was the 4-piston caliper 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. 1968 was also the last year the GTOs offered separate vent, or "wing", windows—and the only year for crank-operated vent windows.
1969
The 1969 model 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.
The previous economy engine and standard 350 hp 400 in³ V8 remained, but the 360 hp engine was dropped in favor of a pair of new Ram Air engines. 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 aluminum intake manifold, larger Rochester QuadraJet four-barrel carburetor, high-lift/long-duration camshaft, forged steel crankshaft 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.
Second generation
1968
GM redesigned its A-body line for 1968, with more curvaceous, "bustleback" fastback styling. The previous 115 inch (292 cm) wheelbase was shortened to 112 inches (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). Pontiac abandoned the familiar stacked headlights for hidden headlights behind the split grille (actually a US$52.66 option, but seen on many GTOs). The signature hood scoop was replaced by dual scoops on either side of a prominent hood bulge extending from the protruding nose.
Powertrain options remained substantially the same as in 1967, but the standard GTO engine rose to 350 hp (261 kW) @ 5,000 rpm. At mid-year, a new Ram Air package became available with freer-breathing cylinder heads, round port exhaust and the 744 cam and 3.90:1 rear differential. Horsepower rating was not changed, although actual output was likely somewhat higher, especially with open exhausts. Another carry-over from 1967 was the 4-piston caliper 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. 1968 was also the last year the GTOs offered separate vent, or "wing", windows—and the only year for crank-operated vent windows.
1969
The 1969 model 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.
The previous economy engine and standard 350 hp 400 in³ V8 remained, but the 360 hp engine was dropped in favor of a pair of new Ram Air engines. 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 aluminum intake manifold, larger Rochester QuadraJet four-barrel carburetor, high-lift/long-duration camshaft, forged steel crankshaft 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.
1970
The Tempest line received another facelift for the 1970 model year. 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 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. Rather than a fixed ratio of 17.5:1, requiring four turns lock-to-lock, the new system varied its ratio from 14.6:1 to 18.9:1, needing 3.5 turns lock-to-lock. Turning diameter was reduced from 40.9 feet (12.5 m) to 37.4 feet (11.4 m).
The Judge remained available as a separate model. 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 on The Judge. Striping was relocated to the upper wheelwell 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 musclecars 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. The GTO remained the third best-selling intermediate musclecar, outsold by the Chevrolet Chevelle SS 396/454 and Plymouth Road Runner.
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