The 2005 Grand Prix is made for those who enjoy driving, and precise handling is central to the vehicle’s satisfying experience behind the wheel. With the wheels wider apart, Grand Prix corners flatter and more confidently. Also, less weight is transferred in the turns and tire loads are more evenly balanced.
At the heart of Grand Prix’s handling is a four-wheel independent suspension featuring MacPherson struts with coil springs, lower A-arms and a 20-mm solid anti-roll bar in the front. Grand Prix’s rear independent suspension features a tri-link coil-over-strut design and a 17.2-mm anti-roll bar on the GT and GTP. A 20-mm hollow anti-roll bar is used on the Comp G package. The result is a sportier ride with a solid, balanced feel. When it comes to stopping power, four-wheel disc brakes are standard on every model. ABS is standard on GT and GTP models; it is optional on Grand Prix models.
Grand Prix’s new family of wheels for 2005 includes a trio of five-spoke, flangeless-design wheel covers and aluminum wheels. The flangeless design pushes the spokes of the wheel to the edge of the rim for a bolder, more prominent look. Sixteen-inch wheel covers are standard on Grand Prix models, and 16-inch aluminum wheels are standard on the GT. Seventeen-inch wheels are available on the GT and standard on the GTP.
Encouraging Grand Prix’s corner-hugging personality are two versions of GM’s venerable 3800 Series III V-6 engine. The naturally aspirated 3.8L V-6 powers Grand Prix and GT models, delivering 200 horsepower (145 kw) and 230 lb.-ft. of torque (305 Nm), while the top-of-the-line GTP is powered by a supercharged version of the 3.8L V-6. Equipped with a fifth-generation Eaton supercharger, which forces pressurized air into the engine to boost power, the GTP’s engine delivers 260 horses (186 kw) and 280 lb.-ft. of torque (380 Nm).
Both engines employ electronic throttle control to provide no-lag engine response, and both are backed by the Hydra-Matic 4T65-E electronically controlled automatic transmission. In California and Northeast states, the ’05 Grand Prix GT’s engine meets SULEV emissions.
Comp G
The Competition Group Package (Comp G), optional on the GTP model, makes Grand Prix capable of attaining .83G of lateral acceleration in turns, making it the best-handling car in its class. StabiliTrak Sport, a segment-exclusive four-wheel vehicle stability enhancement system, also is included in the Comp G package, which features a sports-tuned suspension, 3.29 axle ratio, performance tires and Magnasteer II.
StabiliTrak assists the vehicle in maintaining the driver’s intended path by applying a brake force at any corner of the vehicle independent of the driver’s use of the brake pedal. StabiliTrak uses an accelerator pedal position sensor, a brake master cylinder pressure sensor and a steering wheel angle sensor as inputs to interpret the driver’s desired path and whether to accelerate or decelerate the vehicle. StabiliTrak also uses these sensors plus a lateral accelerometer and yaw rate sensor to determine the vehicle’s actual path. If the difference between the driver’s desired path and the vehicle’s actual path becomes great enough, StabiliTrak takes appropriate action to assist the driver with maintaining the desired path. If the vehicle begins to “snowplow,” or understeer, StabiliTrak applies the inside rear brake to help turn the vehicle. If the vehicle begins to fishtail, or oversteer, StabiliTrak applies the outside front brake to straighten the vehicle. StabiliTrak is integrated with the traction control and ABS systems.
Also standard with the Comp G package is TAPshift (Touch Activated Power), an industry-exclusive feature providing all the fun of driving a manual transmission while retaining the convenience of an automatic.
Convenience, comfort and safety
Standard comfort features include a climate control that features manual settings and heating and cooling outlets for the rear seat. Also standard on all Grand Prix models is a center console with integral armrest, storage compartment and two power outlets; rear reading lamps; assist grips; electronic cruise control; power programmable door locks; a driver information center; remote keyless entry; AM/FM stereo with CD player; and rear-seat pass-through.
The rear doors swing open 82 degrees (a segment first), making it easier to enter and exit the rear seat and to load bulky items like a large TV or computer box. An extra-wide trunk opening also makes it easier to load items such as bicycles or large boxes. And, with the optional fold-flat front passenger seat coupled with the standard 60/40 split-folding rear seats, items as long as a 9-foot (2.7-meter) ladder, lumber or even a kayak can fit inside the Grand Prix with the trunk closed. GT and GTP models include a trunk storage net.
Crash-avoidance features on Grand Prix include four-wheel anti-lock brakes (standard on GT and GTP models), an enhanced traction system available on Grand Prix and standard on GT models, all-speed traction control on the GTP, and daytime running lamps with automatic exterior lamp control. GT and GTP models have standard tire inflation monitoring systems, which warn if a tire becomes under-inflated.
The head-up display (HUD) allows the driver to operate at night in "stealth" mode, enabling the driver to navigate with the instrument lights off for better night vision. HUD features include speed, compass, entertainment functions, warning messages and shift indicator for TAPshift.
Safety belts remain the primary and most effective form of occupant protection. All seating positions in the Grand Prix have three-point safety belts. Grand Prix also has dual-stage frontal air bags for supplemental protection for front seat passengers. Dual-stage frontal air bags are designed to help reduce the risk of air bag-induced injury. When the air bag system’s control unit detects an impact, it determines whether the crash is severe enough to trigger a deployment, and whether the primary amount of inflation is sufficient. The primary stage alone will deploy in most frontal impacts requiring the supplemental protection of an air bag, while a secondary stage is designed to deploy in more severe frontal collisions.
Optional head curtain side air bags act like a protective curtain when deployed, unfolding from the roof rail between the A-pillar and side window header. When the bag deploys in a moderate to severe side impact, it is angled somewhat toward the window to help provide protection for front- and rear-seat outboard passengers.
Grand Prix also is equipped with LATCH (Lower Anchors and Tethers for CHildren) system anchors for child safety seats. This system provides two lower anchors and a top tether anchor to be used to secure a child seat to the vehicle seat structure. These anchorages are designed to make it easier to properly install compatible child safety seats.
OnStar is now standard on all Grand Prix models and features new, sixth generation hardware with digital and analog coverage. OnStar’s Gen 6 hardware also includes upgraded hands-free voice recognition capabilities including more intuitive continuous digit dialing and improved voice recognition accuracy. OnStar is the leading provider of in-vehicle safety, security and information services in the United States and Canada. Using the GPS satellite network and wireless technology, OnStar
features core safety services and OnStar Personal Calling that allows drivers to make and receive hands-free, voice-activated phone calls using a powerful three-watt digital/analog system and external antenna for greater reception.
Text and photos courtesy of General Motors
