A new dual headlamp arrangement set in
squared- off bezels replaced the quad headlamps seen before, and a pair of
rectangular grille openings housed blacked- out vertical plastic mesh inserts, which
were exclusive to the GTO. A prominent nose beak flowed back into a large
ironing-board contour on the hood, which also featured a pair of NACA scoops.
These scoops were intended to be part of a factory Ram Air system, but ended up
being non-functional, save for a handful that managed to get out through the
parts network.
Rather
than go with the GR70-15 radial tires used on the Grand Am, the GTO relied on
bias-ply F60-15s, which had a shorter, stiffer sidewall and an aggressive
contact patch. Standard 15x7-inch steel wheels used a baby moon hubcap, though
Deluxe wheel covers. Rally II or Honeycomb wheels were optional.
The body sides were perhaps the most
interesting features of the new-generation GTO. Bladed front-fender contours
flowed back into the middle of the door, while a similar contour was used for
the rear quarter-panels; the trailing edge providing the flattened shape of the
rear deck, which used single, rectangular tail lamps and a large, jutting
chrome rear bumper with energy absorbers. Combined with a semi-fastback
roofline, the look was unlike any Pontiac that came before it.
The '73 GTO was a $368 option for LeMans
two-doors and could be had in two body styles, the only real differences being
the shape of the quarter windows. The first was the lower-level Colonnade
coupe, which featured a large, open triangular shaped rear quarter glass. It
fit in the model line-up in the same way as the LeMans pillared coupe.
The second available body style was the
Colonnade Sport Coupe, which featured the sportier louvered rear-quarter
window. It gave the GTO an aggressive appearance, but came at the expense of
visibility, as the glass opening was significantly smaller and created blind
spots.
From
the front, the GTO shows a little of its former swagger, with a dual-scoop hood
featuring the NACA duct design. Though some factory literature incorrectly
lists them as “NASA ducts,” they actually go back much farther than that, to
its predecessor, the National Advisory Committee on Aeronautics, which came up
with the design in 1947.
The GTO interiors, like their LeMans parent
series, started with a cloth and vinyl-bench seat standard, with a vinyl bench
seat as an option, as well as bucket seats, console, and floor shifter. A
two-spoke steering wheel was standard, with Custom Sport and Custom Cushion
wheels optional.
The '73 GTO's dash was new and heavily
padded. The walnut wood accents set of two large gauge openings and one smaller
opening between them. The left gauge pod housed the warning lamps for voltage,
coolant temperature, and oil pressure. The smaller center opening housed the
fuel gauge. The third opening was the 120-mph speedometer. An optional gauge
cluster added an 8,000-rpm tachometer and a clock in the left pod, and coolant
temperature and fuel gauges in the center pod.
Powertrains
With the deletion of the Super Duty 455 at
the last minute and the 455 H.O. ending production in '72, only pure-Pontiac
D-port engines were available in the GTO. Performance continued to drop with
the addition of a new Exhaust Gas Recirculation (EGR) system, which
reintroduced a small amount of exhaust gas back into the combustion chamber to
reduce combustion temperatures and oxides of nitrogen (NOx) production.
Aside
from the stripes and GTO callouts on the fenders, there are not many visual
cues to distinguish the GTO from a LeMans Sport. The loss of the 455 Super Duty
no doubt cut into sales, as buyers insisting on that engine had to go with a
Firebird Formula or Trans Am.
Pontiac found a clever, if not illegal, way
to raise the performance back up a little. Knowing that EPA emissions tests
lasted 50 seconds, sneaky Pontiac engineers designed a solenoid that would shut
off the system after 53 seconds. The EPA found out, were very upset, and
ordered a redesign of the system to eliminate the timer shutoff. The later
engines were re-coded and painted in a darker blue to make them easy to
identify compared to the earlier versions.
