New for 2004

Objectives for enhancing the 2004 S2000 chassis included simultaneously improving both at-the-limit track performance and the street performance during everyday driving conditions. Honda engineers re-visited the performance of the tires and suspension to improve overall handling of the S2000 and enhance "limit controllability." I can attest to the challenge in controlling the S2000 at its limit as the car would quickly snap once its limit was exceeded. Honda has sought to improve the predictability by increasing tire size and body rigidity, minimize rear suspension bump steer qualities, and lower the rear roll center.

• Revised spring, shock absorber and stabilizer bar rates
• 17-inch wheels and tires (increase from 16-inch)
• Optimized rear toe settings
• Enhanced suspension bushings
• Revised Electrically Powered Steering (EPS) programming with optimized steering gearbox ratios and enhanced steering bushing rigidity
• Body rigidity increased
• Brake pedal rigidity and build-up feel increased
• Brake pads upgraded to enhance brake fade durability and master cylinder power ratio optimized

Benefits from Suspension Changes

• Improved cornering grip
• Body torsional rigidity increased for enhanced vehicle stability
• Greater stability over road disturbances
• Enhanced stability on wet surfaces
• Linear steering feel increased with reprogrammed EPS system
• Dynamic braking qualities improved

Highly Rigidity Body and X-Bone Frame

For 2004, S2000 torsional body rigidity has been further increased by 10-percent in the front and 9-percent in the back through the use of four strategic sets of new reinforcements on the body and chassis.

• Reinforcements have been added to the rear wheel house bulkhead
• Reinforcements have been added to the front cross members
• Brackets have been added to the front upper A-arms (this seems to address an issue where some racers have observed that their A-arm brackets were showing signs of fatigue from extreme stress brought by race tires)
• A performance rod has been added to the front cross member
• Curb weight is 2835 lbs. (24 lb increase)

Benefits from the increase in body rigidity include decreased response lag during steering input, improved steering linearity through enhanced rigidity, and reduced body flex, which can diminish handling qualities.

Compact (In-Wheel) 4-Wheel Double Wishbone Suspension

For 2004, modifications have been made to enhance performance at the limit, improve control and reduce unwanted sensitivity to internal and external forces during acceleration and braking. Overall suspension geometry has been enhanced by changing the initial rear toe and bump steer settings, lowering the roll center, and optimizing the shock absorbers, spring rates, stabilizer bar and body rigidity.

From a handling standpoint, the 2004 S2000 features improved steering response and accuracy with a more linear overall feel. At-the-limit controllability has also been enhanced along with vehicle stability under heavy accelerator on/off situations.

A 1.04x0.18-inch (26.5x4.5mm) front stabilizer bar and a 1.00x0.18-inch (25.4x4.5mm) rear bar contribute to the S2000's and enhanced steering linearity and quality. The bars connect to their respective suspension arms via ball-jointed links.

Alignment Settings

Mono-Tube Shock Absorbers

The 2004 S2000, with the improvement of damping forces, reduces the feel of road disturbance while maintaining ride quality.

Electric Power Steering (EPS) System

To achieve higher performance, enhancements have been made to the steering system that match the new tire sizes, suspension settings and body rigidity specifications. Also, the rigidity of the steering mount bushings have been increased and the EPS computer has been reprogrammed, resulting in a more linear steering feel.

High-Performance, 4-Wheel Disc Braking System

The front pad material is Jurid632, a high-performance, low steel, fade-resistant type that enhances the brake pedal's solid feel and helps increase resistance to brake fade. Brake-pad area is 42 square centimeters for the front pads and 27.9 square centimeters for the rear-brake pads.

A 7.8-inch, tandem-vacuum servo-assist unit is used because it offers the best balance between pedal feel (stiffness) and assist. Braking bias -- front-to-rear -- has also been optimized so that the front and rear brakes operate at maximum braking efficiency during heavy braking.

Anti-Lock Brake System (ABS)

The system uses the memory capacity of the system's Electronic Control Unit (ECU) and allows the system to better estimate vehicle speed, which gives it better control in the lower-slip range. This contributes to superior braking efficiency and stability. For the 2004 S2000, with improvement of both hardware and software in the compact ABS modulator, memory capacity has increased and new program logic has been added which enhances braking efficiency and reduces the weight of the system.

Wheels and Tires

Larger wheel and tires for the 2004 S2000 improve overall grip and cornering performance. The S2000 features Bridgestone Potenza RE 050 215/45R 17 87W front tires, mounted on 17 x 7.0 jj aluminum-alloy wheels. The rear tires are 245/40R 17 91W and are mounted on 17 x 8.5 jj aluminum-alloy wheels. A space-saver spare tire is in the trunk.

Source: Honda PR