Honda S2000

The Honda S2000 is a roadster manufactured by Honda Motor Company since April 1999. The car continues in the tradition of lightweight roadster "S" cars such as the S600 and S800. Like previous S cars, the name of the S2000 comes from its engine displacement of approximately 2000 cc (although Honda would later introduce a 2200 cc model, still under the S2000 name). From its inception in 1999 to 2003, S2000s were manufactured in Honda's Tochigi plant. S2000s since then have been manufactured in the Suzuka plant.

Design

Honda created the S2000 to mark the company's 50th year. The rear wheel drive platform continued in the tradition of the car's predecessors, S600 and S800 in spite of the fact that most Honda vehicles manufactured today use front-wheel drive. Power is delivered via a Torsen limited slip differential mated to a six-speed manual transmission.

The S2000 is constructed using an X-bone monocoque frame that is extremely rigid, thus improving handling, road noise, and steering feel and feedback. Other features included double wishbone suspension, electronically-assisted steering, integrated roll hoops and an electric top that takes 6 seconds to operate, touted as the fastest opening top among all convertibles.

Models

The car was originally launched in 1999 as a 2000 model, and was sold through to 2003. It featured 16" wheels with Bridgestone Potenza S-02 tyres. The 2004 model introduced newly designed 17" wheels and Bridgestone RE-050 tyres along with a retuned suspension that reduced the car's tendency to oversteer. The spring rates and shock absorber damping were altered and the suspension geometry modified to improve stability, by causing toe-in under cornering loads. In addition, cosmetic changes were made to the exterior with new front and rear bumpers, revised headlight assemblies, new LED tail-lights, and oval-tipped exhausts. The 2.0 L engine was also revised. At the same time, Honda introduced a 2.2 L variant to the North American market with more torque and redline reduced to 8,200 rpm.

The 2006 model introduced a drive by wire throttle and a Vehicle Stability Assist system. Interior changes included revised seats, additional stereo speakers integrated into the headrests, and additional headrest padding where previous seats had helmet depressions and screens. The 2.2 L engine was also introduced to the Japanese market during this time.

Powertrain

The first S2000s (2000 to 2003 models) came equipped with a 2.0 L (1997 cc) F20C I4 engine producing 240 hp (179 kW) at 8,300 rpm and 153 ft·lb (208 Nm) of torque at 7,500 rpm. Though the Japanese models were quoted with additional 10 hp due to a small difference in engine compression ratio, all engines were the same.

Because of its high-revving nature (9,000 rpm redline from 2000 to 2003 models and 8,200 rpm in 2004 onwards models), it is one of the few naturally-aspirated engines to produce over 100 hp/L. The compact and lightweight engine, mounted entirely behind the front axle, allowed the S2000 to obtain a good front/rear weight balance and low rotational inertia for improved handling.

Following criticism about a lack of low-down torque, Honda introduced a variant of the F20C engine to the North American market in 2004. The stroke of the motor was lengthened (increasing displacement to 2.2 L), resulting in the F22C1. As a result, the redline was reduced to 8,200 rpm (mandated by the longer travel distance of the pistons). Peak torque was increased by 6% and the F22C1 was quoted by Honda as having more torque at lower rpm than the F20C, although officially the power output remains the same between the two engines. Initially, the F22C1 was intended only for the North American market, but it was also introduced to Japan in 2006.

In addition to the displacement change, for the F22C1, Honda changed the transmission gear ratios, by shortening the first four gears and lengthening the last two. Another change was the inclusion of a clutch release delay valve, to improve drivetrain longevity by reducing shock loads.

Fuel economy

The official fuel economy figures for the 2006 Honda S2000 produced by the United States EPA are as follows:

• Fuel Type: Premium Unleaded
• City: 20 miles per US gallon (MPG)
• Highway: 26 MPG
• Combined: 22 MPG

Awards

• The S2000 was on Car and Driver's Ten Best list for 2000 through 2002 and 2004.
• The S2000 was the highest-ranked model in the J.D. Power and Associates 2004 Vehicle Dependability Study's "Premium Sports Car" class, and consistently holds one of the top three positions.
• The F20C engine won the International Engine of the Year award in the "1.8 to 2 liter" size category for five years from 2000 through 2004.

Reviews

The S2000 has received much praise from critics and motoring journalists and has received favourable reviews from publications like Car and Driver, Car magazine, the Los Angeles Times and Road & Track magazine. Among the features highlighted include the high output of the engine, the high-rpm redline and the smooth gearbox.

Criticism

Despite the high power output of the engine, the torque of 153 ft·lb (207 Nm) in the 2.0 L version and 162 ft·lbf (220 Nm) in the 2.2 L version was quite low even compared to other sports cars with four-cylinder engines. One reviewer described the 162 ft·lbf as "measly" [2]. Another complained that "High revs and a lack of low-down punch were only two of the major drawbacks" of the vehicle [3].

By comparison, the 1989 Porsche 944's four-cylinder engine produces 206 ft·lbf (279 Nm) as a result of its higher displacement of 3.0 L. In addition, many of the S2000's competitors (BMW Z4, Porsche Boxster, Nissan 350Z convertible) offer engines which produce as much or more power as well as more torque with more cylinders and/or higher displacement) and competitors like the Lotus Elise achieve better performace with a higher power to weight ratio even though they had less engine power.

In addition, the torque curve of the engine is unusually steep [4], with just 25% of the engine's torque available below 3000 rpm where most driving is done and only about 8% available from idle.

Changes to the 2004 model brought a revised suspension and a lower redline (lower redline and 2.2L Engine initially on US model only). This triggered some criticism from those who saw the original 9000 rpm redline as a key selling point.

Another area where the car was singled out for criticism was handling and roadholding. Many drivers commented on the early cars' tendency for snap oversteer, especially in wet or otherwise slippery conditions. In the words of one reviewer, the car was descriped as "unpredictable at its limit, prone to enthusiastic oversteer" [5]. Another reviewer complained that "oversteer came on pretty suddenly" [6] and that the car was "was known to be unpredictable at its limit" [7]. Still others said "Squeeze the throttle too hard, though, and all hell would break loose. It would snap into oversteer, and only lightning-quick reactions could save you from an excursion into the undergrowth" [8]

The AP2 model, with its revised suspension and wider tires reduced this characteristic but did not eliminate it. The introduction of electronic stability control in 2006 was deemed necessary to further reduce this tendency. Still, some reviewers remained unconvinced, saying of the updated car that "the rear is still eager to break away with little provocation" [9]

Another criticism of the S2000 is the way the car is geared. The short gearing allows the car to accelerate reasonably quickly, yet it forces the occupant(s) to endure high-engine revs and correspondingly high levels of engine noise while travelling at highway speeds. In 6th gear, the car is only capable of around 18 mph/1000 rpm - at 75 mph, the engine would be running at roughly 4200 rpm. For comparison, most performance cars tend to achieve about 25 mph/1000 rpm in top gear and some (e.g. Chevy Corvette and Dodge Viper) are significantly higher.

References

1. ↑  Car and Driver review of the 2003 S2000
2. ↑  Carpages overview of the 2004 S2000

External links

• S2000 Official Site (US)