For 1973 the GTO remains as an option and not a car. The option is available on the LeMans and LeMans Sport Coupe two-door Colonnade hardtop and is fitted with all the goodies that were responsible for the image created by the original GTO. There's a blacked-out grille; dual hood scoops; optional (functional) Ram Air; super suspension; GTO identification; Moon-styled hubcaps with G-60 black tires; chrome duals and seven-inch wheels. The base engine is the 400 four-barrel but you can option the supermarket 455-inch four-barrel and the King of the Street Super Duty 455. There's also an option list that immediately recalls the good old days. And, it's all legal-eagle and insurable.
The optional 455-inch four-barrel engine isn't much of a performance engine and actually offers little more for the enthusiast than the base 400-incher. The SD-455, however, is something else. It pumps out 310 net horsepower, runs on 91 octane fuel (it runs much better with timing kicked up and the tank filled with Sunoco 260!) and passes all federal and state emission and noise laws. And, it's actually no less economical to operate under normal driving use than the consumer-oriented 455 four-barrel engine. It can be had with air conditioning, full power, 3.42 limited slip rear and a choice of M-20 four-speed or three-speed Turbo Hydro transmissions. Features that make the SD-455 a genuine performance engine include four-bolt main caps; screw-in oil plugs; provision for dry sump lubrication; nodular iron crank; forged steel rods with 7/16-inch bolts; forged aluminum pistons with high-rev rings; HD oil pump; flow-bench-designed heads; high-lift cam with big valves; big headers and exhaust pipes and a revamped Quadrajet intake system.
New option this year is NASA scoop treatment which is standard on the GTO. Coupled with the optional ram air package the scoops direct cool fresh air to the Quadrajet four-barrel. It's a nice package with the Super Duty 455 engine. Head Turning Power is unreal.
When the engineers designed the suspension for the GTO it was almost as though they had our very own Joe Oldham in mind. Joe has little use for anything other than the ultimate handling vehicle and he doesn't care how harsh a car rides as long as it'll go around a handling course or a skid pad with only minimal traces of sway or roll. Joe likes his cars hard riding, positive handling and totally predictable. In most cases, the "optional-optional" factory suspensions aren't stiff enough for him. The GTO receives the Oldham Seal of Suspension Approval! It isn't as harsh as you might think, but there's little doubt that the GTO can take the highest lateral G loads possible in a car of this size and weight. If you are looking for more of a compromise ride the Grand Am would be a far better choice than the GTO.
Even on a wet road surface the GTO is an outstanding handler. Now suspension is the firmest ever offered in a production intermediate and really gets the job done. Much care must be exercised on wet roads because of aquaplaning effect of 60-series tires.
The new GTO "OM" (Oldham Maximus) suspension makes use of a 1 1/8-inch front sway bar and a one-inch rear bar. The older cars had a one-incher up front backed up by a 7/8-inch rear bar. The thinking here was to keep the standard spring rates and control the roll stiffness via the use of front and rear stabilizer bars to maintain a reasonably good ride. Harshness has been dampened but not enough to make the ride appeal to the pseudo-enthusiast's tastes. Super fat 15-inch 60-series tires are used for both appearance and for maximum traction. The engineers also feel that 60-series tires offer more cornering power with the GTO's suspension than do radials. Radials are used to a fantastic advantage with the calmer Grand Am suspension, but the engineers feel that they don't work as well as the 60-series tires with the GTO suspension. Radials are also more expensive and do not fit in with the basic GTO marketing concept.
The '73 GTO offers enthusiasts everything the golden oldie GTO did, plus all the new technology gleaned since those cars were on the drawing board. You have to pay more for the '73 version, but we don't believe this will prevent enthusiasts from signing on the dotted line. It's the most refreshing car to drive since solid lifters, Holley carbs and real engines were "discontinued until further notice." We believe Pontiac's GTO has far surpassed its ontogenic beginning!