Porsche Boxster brought mid-engine performance and concept car styling to the street. For 2003, the roadster has undergone discreet refinements that enhance both its performance and its styling. But in typical Porsche fashion, even the styling changes contribute to improved performance.
Style with substance
The styling changes include a new roof with a glass window and electric defroster, new lower front and rear fascia and a new rear spoiler. These changes are much more than mere cosmetics. Each of the changes improves aerodynamic efficiency by enhancing airflow to the engine, around the exhaust system or over the redesigned spoiler.
Also new for 2003 are engine enhancements that increase the output of the Porsche Boxster's 2.7-liter horizontally opposed six-cylinder "boxer" engine to 225 horsepower (SAE). The car now accelerates from a standing start to 100 km/h (62 mph) in only 6.4 seconds, an improvement of two-tenths of a second compared to the 2002 model.
But the engine modifications improve more than just the 2.7-liter's power output. They also enhance the engine's all-around efficiency so that the "boxer" returns better fuel economy, than the 2002 model.
The Porsche Boxster's performance can be improved even more through the availability of new lightweight wheels.
Other changes for 2003 include a new pop-out cupholder, a lighted and locking glove compartment, more uniform dash-mounted switchgear, new interior trim colors and remote unlocking front and rear trunks.
2003 Porsche Boxster
Also new are Porsche Communication Management systems (PCM) that incorporates tuners, CD player, navigation system and trip computer, all connected to each other through the new Media-Oriented Systems Transport (MOST) digital databus.
"True to its Porsche heritage, when it came time for the Porsche Boxster to undergo subtle styling changes, the underlying reason was to enhance performance," says Frederick J. Schwab, president and CEO of Porsche Cars North America Inc. "Whether it's the more powerful engine or the way adding a glass window improves airflow to the rear spoiler, the car's style and substance work very well together."
New top with glass rear window
The Porsche Boxster's new top has a steeper angle along its rear section and provides a contour that's very similar to that of the Porsche Boxster's optional aluminum hardtop. The new shape is provided by an additional, fourth roof bracket above the new glass window. The glass window comes with electric heating to provide improved visibility in cold and damp weather. Even with its fourth roof bracket and new glass window, the Porsche Boxster's top still features electric kinematic power and opens or closes in 12 seconds.
The new roof is lined and has optimized seals to minimize noise inside the car when the top is up.
The roof is designed so that the rigid, magnesium frame that forms the front edge of the roof provides protection for the glass window when the roof folds away above the engine compartment.
Redesigned rear spoiler
The top's new shape enhances airflow to the Porsche Boxster's redesigned rear spoiler. The spoiler fits smoothly into the shape of the body when retracted, and then lifts automatically into position at 75 miles per hour (120 km/h) to keep the car stable by reducing rear axle lift at Interstate and Autobahn speeds. The spoiler then retracts at 50 mph (80 km/h).
Adjacent to the rear spoiler are smoked lenses for the rear directional signals. Beneath the rear spoiler is a redesigned oval tail pipe flanked by a new and more aerodynamically efficient lower rear facia. The rear fascia has two wide openings that allow better cooling airflow around the Porsche Boxster's exhaust system.
Airflow also improves at the front of the 2003 Boxster and to the car's 2.7-liter engine.
Beneath the car's front bumper are two new cooling air intakes. The new intakes have greater curvature than the former air intakes, providing a "ram" effect to enhance the flow of air for cooling and aerodynamic efficiency.
The redesigned front fascia also includes a more sharply contoured lower front "lip." A change that owners won't see but will appreciate is a new composite component between the body cross-support and the front body panels. This "cushion" provides additional protection and reduces the cost of repairs should the car bump into a curb while parking.
Airflow to the Porsche Boxster's 2.7-liter engine is enhanced to the engine through revised and now body-colored side vents located just in front of the rear wheel wells. The vent on the driver's side takes in air for the fuel/air combustion mixture while that on the passenger's side provides air to cool the engine compartment.
More powerful engine
This enhanced airflow combines with new VarioCam technology, new Motronic ME 7.8 engine management controls, a "returnless" fuel supply system and improved oil pump to make the Porsche Boxster's 2.7-liter engine more powerful and efficient. For 2003, the "boxer" pounds out 225 horsepower (SAE) at 6,300 rpm, compared to 217 for the 2002 model. The engine's torque figure remains 192 pound-feet at 4,750 rpm.
The engine isn't only more powerful; it's also cleaner and more fuel efficient. With its manual transmission, the Porsche Boxster achieves an EPA city rating of 20 mpg, and 29 on the highway and 11.7 l/100km and 7.4 for Canada. The figures are 18 and 26, 13.3 and 8.3 for Canada respectively, with the Tiptronic transmission.
Formerly, the camshaft could be adjusted up to a range of 25 degrees, but this newest VarioCam technology allows infinite adjustment of the crankshaft angle by up to 40 degrees. This reduces charge cycle losses, improving power, mileage and keeping exhaust emissions to a minimum. Porsche was the first manufacturer to introduce this integrated design, which was launched in the 911 Carrera.
With VarioCam, intake camshaft timing is fully variable through a wing-cell adjuster fit directly on the camshaft drive sprocket. Oil pressure is used to turn the position of the inner wing-adjuster wheel versus the outer sprocket by up to 40 degrees of crankshaft angle. Because the intake and exhaust camshafts are driven directly via a roller chain, this new system makes redundant the conventional three-stage chain drive between the crankshaft and the camshaft.
Porsche's patented VarioCam can respond quickly to any sudden need for power or, conversely, to a more reserved style of driving, say in city traffic. This is possible because of the way it can make precise adjustments to valve opening and closing times. When running under part load, the intake camshaft is set to an earlier opening point. The residual gas remaining in the combustion chamber helps to reduce fuel consumption. When running under full load, the engine builds up maximum output through the small overlap in the opening and closing times. Maximum torque is provided by extended valve overlap and the earlier conclusion of the intake period.
Masterminding this system is the new Motronic ME 7.8 engine management program that was developed for the Porsche 911 Turbo. This system was conceived specifically for such high-performance requirements. It measures such parameters as engine speed, pedal position, engine oil and coolant temperatures and gear selection. It calculates the requisite position of the intake camshafts, and synchronization of intake camshafts on both rows of cylinders. This synchronization is ensured by its intelligent controls as the system intervenes in the fuel/air mixture formation and ignition.
Even with its boost in output, the engine itself is so strong that it didn't need to be reworked. One secret of the strength of the Porsche "boxer" engine is its separate bearing bridge for the crankshaft, which has seven main bearings. This aluminum structure has cast steel support elements that provide a secure foundation for the crankshaft, even in widely varying temperature ranges. The integrated dry sump lubrication system carries over, although the output of the compressed oil pump has been increased by about 5 percent.
"Returnless" fuel system reduces evaporative emissions
The Porsche Boxster's engine also benefits from a "returnless" fuel supply system that reduces hydrocarbon emissions caused when fuel is heated prematurely as it flows back and forth to the engine through the traditional delivery system. Porsche engineers have developed a new and maintenance-free "returnless" fuel system that incorporates a pump, filter and pressure regulator in the fuel tank. The result is that only the fuel that is actually needed for optimum combustion is pumped to the engine. Excess fuel no longer enters the circuit and thus is not exposed to premature heating. A bonus from this system is that there is no need to replace the fuel filter as part of an owner's routine maintenance.
For 2003, the Porsche Boxster sounds even better while producing more power using less fuel and with reduced emissions. Porsche engineers have carefully modified the interior of the car's muffler to improve the car's "acoustic presence." The length and diameter of the various pipes and the perforation of the inner pipes were changed to satisfy not only legal sound limits but also the well-trained ear of the automotive enthusiast. The result is a muscular mix of sound that underscores the Porsche Boxster's increased power and performance.
Lighter wheels reduce unsprung weight
While the chassis, suspension (except for the application to the Porsche Boxster of the Boxster S's higher-rate shock absorbers) and brakes carry over from the 2002 Boxster, the car's handling can be enhanced with new, optional light-alloy wheels. The Porsche Boxster rides on standard 16-inch wheels, but 17- and 18-inch wheels are available as options. These optional wheels reduce unsprung weight and ensure smooth and sensitive response from shocks and springs. The 17-inch wheels reduce unsprung masses by more than half a pound per wheel. The 18-inch wheels, which were developed for the 911 Carrera, cut unsprung weight by more than five pounds per wheel. This weight reduction results in even crisper handling.
Also optional on the Porsche Boxster is a sport suspension package that improves the car's already amazing responsiveness through shorter and firmer springs, firmer and more responsive shocks and larger anti-roll bars.
There are several changes to the Porsche Boxster beneath its new electrohydraulic roof. For 2003, the list of standard equipment includes a new, 911-style cupholder that pops out of the instrument panel and a lighted and locking glove compartment. The cupholder is located just below the center air conditioning outlet. The glove compartment is located beneath the passenger-side airbag and has a capacity of 305 cubic inches (five liters). The glove box lock is connected to the car's alarm system.
The air-conditioner and heat controls have been moved from the console to the dash for easier accessibility and use, and instead of black leather, the steering wheel, gearshift lever, door handles and handbrake lever are covered in the same color leather as the seats. Color Porsche crests in the standard three-spoke steering wheel and the car keys add a classic design touch.
Communicating at the speed of light
Porsche's new Communication Management system (PCM) comprises tuners, CD player, navigation system, and trip computer, all linked through Media-Oriented Systems Transport (MOST) digital databus. The MOST system incorporates light-wave conductors that exchange data between the individual components without loss of quality and at ultra-high speeds.
PCM includes a 5.8-inch color screen with its 16:9 aspect ratio and 12-position keyboard for easily and efficiently entering radio frequencies. The system assures excellent audio quality.
The navigation module provides such features as road junction zoom-in, dynamic navigation to avoid congestion, map scrolling so you can see beyond your current position, tour planning with the ability to memorize as many as eight destinations in a row and a CD-ROM system that can be used for the navigation system or for music.
Remote trunk locks
Also new for 2003 are remote unlocking front and rear trunks. Two trunks? That's right. Although it's a true roadster, the Porsche Boxster's mid-engine placement provides space for storage areas at both ends of the vehicle. Together, these trunks offer an impressive 9.1 cubic feet of cargo capacity.
The Boxster basics
While the Porsche Boxster has been updated and upgraded for 2003, most of the basic components that have made the car so popular with sports car buyers remain unchanged.
The 2.7-liter six-cylinder engine continues to provide real-world performance. It achieves its 192 lb.-ft. of peak torque at only 4,750 rpm and sustains it to nearly 6,000. Just as important, the powerplant delivers a significant 147 lb.-ft. of torque at only 1,750 rpm for powerful response even at low engine speeds.
In addition to the Porsche-patented VarioCam technology, the engine uses a lightweight aluminum cylinder block and heads and patented LOKASIL high-silicon cylinder liners that reduce friction and wear to such a level that Porsche can recommend a 15,000-mile (24,000 km) oil change interval and a 30,000-mile (48,000 km) oil filter change interval.
Two five-speed transmissions
Porsche Boxster customers can choose between the precisely shifting standard five-speed manual transmission and the optional Tiptronic S five-speed automatic transmission. With the advanced Tiptronic S, the driver can place the shift lever into "D" and let the transmission do the shifting, or shift into "M" and control gear shifts with steering wheel-mounted thumb switches.
In automatic mode, Tiptronic S uses one of several programmed shift maps to respond to the driving style. For example, during leisurely driving, Tiptronic S will up shift early to provide a quiet ride. Quicker stabs at the gas pedal will call up a sporty shift program, which holds each gear longer for response and power. Even while in automatic mode, the computer-controlled Tiptronic S responds like a driver working a manual transmission, downshifting or holding lower gears when cornering and driving on hills. Tiptronic S also allows the driver to select manual mode by pressing an up- or downshift button, even with the shift lever in the "D" position.
Inspired by racecars
The racecar-inspired mid-engine layout concentrates the car's mass near its center, providing quick response to steering inputs. Four-wheel independent suspension features a Porsche-optimized MacPherson-strut design for rigidity and aluminum components for low unsprung weight. Front and rear stabilizer bars and dual-tube gas-charged shock absorbers provide flat cornering.
Standard power rack-and pinion steering yields a quick 2.98 turns lock-to-lock and a tight 35.8-ft. (10.9-meter) turning circle.
A "staggered" wheel/tire array (wider wheels and wider, lower-profile tires on the rear) contributes to neutral handling in the Porsche Boxster. The standard aluminum alloy wheels measure 16 x 6 inches in front and mount 205/55 ZR16 tires; the 16 x 7-inch rear wheels mount 225/50 ZR16 tires. Optional 17- and 18-inch wheel/tire packages enhance the already precise handling.
The Porsche Boxster stops with four-wheel vented disc brakes with ABS 5.3 anti-lock control. Derived from the Porsche GT1 racecar, one-piece "monoblock" brake calipers reduce heat and unsprung weight. The front discs measure 11.7 inches in diameter and 0.95-inch thick (298 mm x 24 mm). The rear discs measure nearly as large - 11.5 inches in diameter and 0.8-inch thick (292 mm x 20 mm).
Extensive standard and optional equipment
The Porsche Boxster comes equipped with extensive standard comfort and convenience equipment, including:
Optional equipment includes:
Bose digital audio
Bose audio equipment was introduced in Porsches for 2002 and features equipment custom-engineered for each Porsche model. The new Bose automotive music systems combine balanced stereo, a panoramic sound stage, deep bass and smooth frequency response to produce lifelike music reproduction even in the challenging environment of a car interior. The Bose sound systems employ digital amplifiers to provide clean, uncolored sound at any listening level. In the Porsche Boxster, an array of 10 advanced loudspeakers blends seamlessly into cabin trim, raising and widening the sound stage and ensuring balanced stereo. Powerful bass speakers are concealed in customized enclosures to furnish superb performance within limited cabin space.
Safety by design
Safety in the Porsche Boxster starts with the body structure, which features front and rear crush zones that protect a reinforced passenger compartment. Boron steel tubing reinforcements inside the windshield header and A-pillars along with supplemental safety bars behind the seats provide additional safety in rollover accidents. The supplemental safety bars feature soft-touch covering for a high-quality appearance and tactile feel.
Supplementing the three-point inertia-reel seatbelts, the Porsche Boxster features seatbelt pretensioners and load limiters as well as dual front airbags and the Porsche Side Impact Protection System that includes door-mounted side airbags, boron-steel door reinforcement beams, and energy-absorbing door panels. The 30-liter capacity side airbags provide additional protection for the chest, head, and pelvis.
At a customer's request, a U.S. Porsche dealer can install a system that deactivates the passenger airbags when a U.S. Porsche-approved child seat is used. The system features a cross brace with belt lock in front of the passenger seat. Buckling the special child seat into this brace deactivates the airbags. To install the system, the dealer also must reprogram the airbag control module.
Porsche Stability Management
The optional Porsche Stability Management system (PSM) can help keep the car going in the direction the driver steers - on slippery or dry road surfaces. PSM uses data from several sensor inputs to detect a loss of grip at the front or rear. The system can reduce instability by applying braking to individual wheels and, if necessary, altering engine power. In addition, the PSM system also provides a traction control function on slippery surfaces.
The PSM system operates so quickly that most drivers likely will not feel it make corrections. The driver can disengage PSM with a dashboard switch. However, for safety, PSM will engage under braking and then disengage when the driver lifts off the brake. While the system provides dynamic handling aid, Porsche cautions drivers that PSM cannot counteract the laws of physics.
LED interior lighting
All Porsche models feature light-emitting diode (LED) interior orientation lights. One LED provides gentle illumination of the cockpit and center console. An LED on the driver's side door handle illuminates the ignition lock and light switch, and an LED illuminates each door latch.
Optional hardtop and roof transport unit
In addition to the standard power top, a three-piece wind deflector is available to reduce wind buffeting and noise during top-down driving. Other options include an aluminum hardtop with a full lining and a glass rear window with defroster, and an innovative roof transportation system that attaches to the convertible roof (open or closed) or the optional hardtop. Suitable for carrying skis, kayaks, or bicycles, the system will hold up to 165 pounds.
The optional Porsche Communication Management system integrates controls and displays for Global Positioning Satellite (GPS) navigation, an onboard computer and climate control. A 5.8-inch (diagonal) LCD color screen displays all functions.