SAAB 9-5 OFFERS TURBOCHARGED POWERPLANTS AND PERFORMANCE-ORIENTED CHASSIS
DESIGN
Saab Ecopower Turbo Engines
Three engine variants are available in the Saab 9-5 Sedan - a 2.3L four-cylinder light pressure turbocharged engine that has been enhanced to provide 185 horsepower for 2001; a 3.0L V-6 asymmetrically turbocharged engine (standard on SE models); and a potent 2.3L four-cylinder high-output turbocharged (H.O.T.) engine for the 9-5 Aero. All three engines are members of the Saab Ecopower family - which means they are designed to provide a unique combination of responsive performance, low exhaust emissions and high fuel efficiency. One of the most noticeable effects of Ecopower technology is the high torque output achieved at low and mid range engine speeds - providing quick acceleration and strong off-the-line response. Saab's engine philosophy focuses on the force that gets mass moving, a solution that delivers excellent acceleration and passing performance from an efficient, small displacement powerplant.
|
Engine |
Horsepower@RPM |
Max. torque @ RPM |
|
2.3t (9-5 Sedan) |
185 @ 5,500 |
207 lb.-ft. @ 1,800-3,500 |
|
3.0L V6 (9-5 SE) |
200 @ 5,000 |
229 lb.-ft. @ 2,500-4,000 |
|
2.3 H.O.T. (9-5 Aero) |
230 @ 5,500 |
258 lb.-ft. @ 1,900-3,800 (manual) 243 lb.-ft. @ 1,900-4,600 (automatic) |
The 3.0L V-6 is matched with a standard 4-speed automatic transmission, featuring "Sport" and "Winter" shift modes. Both 2.3L four-cylinder Saab 9-5 Sedans come standard with Saab's 5-speed manual transmission. The 4-speed automatic is available as an option.
Saab's Traction Control System (TCS) is standard equipment on all 9-5 Sedans. TCS is an "all-speed" system that modulates ABS braking and electronic throttle to optimize traction at the front drive wheels for enhanced control in inclement weather conditions.
2.3L Ecopower Engine
The Saab 9-5 Sedan's 2.3L light pressure turbocharged engine uses relatively low boost pressure (maximum boost of about 8.0 psi or 0.55 bar) to deliver boost quickly, providing higher torque at low engine speeds. Strong low-end torque also contributes towards safer passing and more relaxed driving, without needing to frequently rev the engine to high rpm.
The 2.3L engine has been programmed to develop optimum power with a very flat and broad torque curve. The power curve peaks at 5,500 rpm, while the torque curve is actually a torque plateau - a completely straight line from 1,800 to 3,500 rpm. In fact, over 70 percent of the peak torque value is developed from just above the idling speed to the electronically-governed redline at 6,000 rpm.
Saab V-6 Engine Features Asymmetric Turbo
The Saab 9-5 was the first car in the world to be equipped with an asymmetric turbocharging system. This engine concept uses one turbocharger on the front cylinder bank, driven by exhaust gases from only those three cylinders. The single highly-responsive Garrett GT17 turbocharger delivers compressed air to all six cylinders in both cylinder banks. Combined with a boost pressure that reaches only 3.6 psi (0.25 bar), this technology allows a patented boost control system that eliminates the need for a wastegate.
The advanced 24-valve 3.0L turbo V-6 engine uses a narrow angle of 54 degrees between the cylinder banks. The engine's strong maximum torque of 229 lb.-ft. at only 2,500 rpm, available all the way up to 4,000 rpm, provides useful performance to reduce passing times and avoid potentially hazardous situations. The high torque also allows longer gearing, which improves fuel economy and reduces engine noise at speed.
9-5 Aero's 2.3L High-Output Turbo Engine
The 9-5 Aero features a similar 2.3L high-output turbocharged engine as the 9-3 Viggen. Again, Saab engineers prioritized the engine's torque output rather than horsepower.
The power output of the Saab 9-5 Aero's engine is primarily attributable to the large, variable boost pressure turbocharger, which produces a maximum boost pressure of 1.4 bar, or 20 psi. This allows the 9-5 Aero to maintain maximum power and torque through nearly all driving conditions - including altitudes approaching 10,000 feet. Saab engineers have designed the engine to withstand the additional stress and heat generated from such high boost levels. Like all Saab turbochargers since 1988, the Aero's turbo is both oil and water-cooled. In addition, the engine features reinforced alloy pistons that benefit from oil cooling jets at the base of the block that spray oil at the underside of each piston. The engine also features sturdier connecting rods, nitrided gudgeon pins and strengthened intake valves. To handle the heat, exhaust valves are made of Nimonic alloy - a high nickel content, heat-resistant alloy used in aircraft components subjected to high pressure and temperature, such as the exhaust nozzles in jet engines.
Saab Trionic 7 Engine Management System
All Saab engines feature the latest version of Saab's Trionic engine management system - Trionic 7. A highly sophisticated system, Trionic 7 utilizes a 32-bit microprocessor capable of two million calculations per second to control Saab's direct ignition, fuel injection, turbo boost pressure and the electronic "drive-by-wire" throttle to enhance engine response and eliminate turbo lag. It allows all engines to provide low emission levels, high fuel efficiency and adaptable power and torque levels, for flexible and responsive driving characteristics.
Chassis Designed for Precise Driving Control
The Saab 9-5's chassis has been designed to provide the driver with optimum control at all times - regardless of the driving situation, the load in the car, or external conditions.
The Saab 9-5 Sedan's chassis utilizes isolated front and rear sub-frames to effectively attenuate disturbances and significantly upgrade its driving refinement. MacPherson struts are retained for the front suspension and a multi-link independent suspension is used in the rear. The springs, roll bars and shock absorbers have been calibrated to retain good handling properties and excellent ride comfort. In addition, the power-assisted steering rack is mounted on the rear of the sub-frame to operate with short tie rods and provide very precise wheel control, creating high levels of response and steering feel.
The Saab 9-5 Sedan is equipped with standard front and rear disc brakes and electronically controlled ABS. The ABS system incorporates electronic brake distribution (EBD) and an integrated electronic traction control system (TCS). As with all Saabs, the ABS system is lightweight and compact with four-channel operation triggered by four individual wheel sensors.
EBD comes into effect under hard braking before the ABS is activated. This balances the friction available at each wheel with the braking forces being applied. It automatically provides optimum retardation and the shortest possible stopping distance.
Saab's Traction Control System (TCS) is standard on all 9-5 models. TCS works in conjunction with the engine management system to prevent the driving wheels from spinning if tire grip is lost. TCS is fully automatic in operation, and is functional at all road speeds, but includes an "off" switch for special circumstances (such as if the driver needs some wheelspin to cut through heavy snow, or when snow chains are fitted). The off-switch will only deactivate the system at low speed (below 40 mph).
9-5 Aero's Performance Enhancements
The chassis of the Saab 9-5 Aero has been developed to harmonize with the high-performance turbocharged engine and provide the driver with a highly responsive driving environment. Compared with the chassis of other Saab 9-5 variants, the Aero's chassis is lower by 10 mm (.4 inch) and firmer. Front and rear suspensions are equipped with heavier anti-roll bars, stiffer springs and harder dampers in order to minimize body roll and improve steering precision, chassis response and driver control.
The Aero's standard 17-inch light alloy wheels with low profile 225/45 R17 performance tires contribute to the car's excellent handling characteristics.
In addition, the brake system is enhanced to match the performance of the engine. The front brake discs have been increased to 12.1 inches (308mm), compared to 11.3 inches (288 mm) on other 9-5 models.
