"There's no doubt that outstanding power and launch feel was the priority for this vehicle right from the start," explained Dave Himmelberg, GTO program engineering manager. "The original GTO was the standard bearer of its class in terms of power - and that's exactly the standard we set for ourselves when developing the modern version.
"Anyone who drives this vehicle is going to know it's a GTO from the moment they turn the key and press that accelerator and hear that throaty Pontiac exhaust note - this car will definitely push you back in your seat."
GM engineers pulled out all the stops to create the GTO's exhilarating power and off-line performance, taking an engine already known to driving enthusiasts for its superb performance and reliability / durability -- GM's award-winning 5.7-liter Gen III LS1 V8 -- and refining it for substantially more power and the low-end torque Pontiac's have always been known for, with special exhaust tuning to emphasize its performance-oriented character.
The LS1 V8 provides the GTO with successful, racetrack-proven performance as well as smooth, quiet operation. Its lightweight all-aluminum construction, including cylinder heads and blocks, provide an excellent power-to-weight ratio.
To achieve outstanding launch capability, GM engineers adopted the LS1 V8's high-lift camshaft (increasing low-end torque, without giving up power). They then took advantage of the engine's torque on the low end and changed the transmission gear ratios and final drive ratio for the kind of launch performance one would expect from a GTO.
In addition to off-the-line launch feel, the higher lift camshaft also boosts torque over most of the rev range by an average 5 percent thereby ensuring great reserves of power for sudden acceleration and freeway passing. Compared to the original camshaft, the new configuration provides 20 ft-lb more torque from idle up to 4400 rpm.
The horsepower increase over the original engine setup results from improved airflow into and through the engine and the exhaust system. This includes:
Increasing fresh airflow through the air cleaner with a larger 100mm diameter inlet pipe;
Reducing exhaust backpressure to a very low static pressure of (40 kPa) with a slightly larger diameter size dual pipe system; and,
An all-new true dual exhaust system. It includes dual catalytic converters, one on each exhaust bank; two small resonators, one between each catalytic converter and the mufflers; and pipes-only running from each muffler all the way to the dual chrome exhaust tips which are packaged next to each other at the rear fascia. The two exhaust gas paths are totally independent all the way from the exhaust banks to the dual chrome tips, which are located next to each other. The resonator / pipe design is to achieve the desired exhaust notes.
On the GTO, the LS1 can be mated to GM's most aggressively geared (M12) six-speed manual transmission. The M12 provides quick, smooth, precise shifts; increases torque multiplication in almost every forward gear for quicker acceleration; and delivers outstanding high-speed performance by providing more usable torque at higher speeds.
The precisely controlled, smooth shifting, electronically controlled Hydra-Matic 4L60-E transmission is standard. Used in all GM light-duty applications, it has a long history of customer-pleasing performance and dependability. In the GTO, its electronic controls are calibrated to provide the performance of a super-sport vehicle.
Both the manual and automatic transmissions use the same low-geared 3.46 final drive axle ratio to maximize off-line acceleration. The GTO also offers a conventional limited slip differential, which increases available traction by using both rear wheels to transfer power when one loses traction.
The 2004 Pontiac GTO is a modern interpretation of the classic performance coupe, emphasizing contemporary styling and total performance. It will be available in Pontiac dealer showrooms before the end of 2003 in limited numbers. Pricing has not yet been finalized but is expected to be less than $35K.
(June 17, 2003)