As the connection between the driver and the road, the new Acura NSX chassis provides high fidelity steering and road feedback. Advanced technologies combine to impart sports car agility at low speeds, with confidence-inspiring stability and predictability at high speeds. The NSX faithfully translates driver inputs under a wide range of driving situations for ultimate handling performance.
- All-aluminum front and rear suspension systems provide precise control through highly rigid construction and precise geometry
- Rigidly mounted variable gear ratio electric power steering (EPS) eliminates the need for hand‑over‑hand steering, once out of the parking lot
- Electro-servo sports brakes (ESB) seamlessly integrate friction and regenerative brake systems to provide a powerful and confident response
- Third-generation active magnetorheological (MR) dampers stabilize tire-to-road contact while at the same time stabilizing major body motions
Suspension
A key attribute of the original Acura NSX was its novel use of a finely-tuned aluminum suspension. The NSX team went back to the fundamentals to design the next-generation NSX front and rear suspension systems.
The all-aluminum, fully independent front and rear suspension systems are mounted directly to the ultra‑rigid multi-material space frame without any floating subframes. Utilizing lightweight yet rigid aluminum alloy components at all four corners, the NSX suspension keeps unsprung weight to a minimum while maximizing each suspension link's stiffness for instant and accurate response.
Front Suspension
The front double wishbone suspension decouples steering disturbances, such as torque steer and steering road kickback by splitting the lower wishbone into two separate links. The all-aluminum front suspension has been optimized with compact and lightweight components and geometry for crisp and communicative on-center steering feel and excellent stability.
Rear Suspension
Featuring lightweight, all-aluminum components, the rear suspension employs a sophisticated independent multi-link design with high lateral rigidity to react faithfully to driver inputs and maintain stability. It minimizes lateral acceleration response delay providing proper lateral response phasing of the rear axle with respect to the front, so stable cornering can be achieved up to and beyond 190 mph (308 kph). Basically, the NSX driver can corner faster with greater confidence and control.
Variable Gear Ratio Electric Power Steering
The EPS system utilizes a variable gear ratio. When on center, the ratio is tuned for optimal high speed control and stability. Off center, the gear ratio becomes quicker for improved turn-in and maneuverability at low and mid speeds while minimizing the need for hand-over-hand steering.
Rigid mounting in a high position and high component stiffness minimize lost motion to help realize faithful road feedback. The EPS exhibits many advantages over an engine-driven hydraulic-based steering system. Like the original NSX, the next-generation NSX applies an EPS system to reduce weight, simplify the layout by eliminating hydraulics and provide the basis to create a customizable driving experience for a wide range of driving conditions.
"It was a huge challenge to create a lively and communicative Electric Power Steering for the driver that would be truly worthy of a next-generation Acura NSX," said NSX Chassis Design Project Leader Chris Dundon. "But by optimizing the mechanical components within the system, plus careful tuning of the software, we were able to achieve our goal of delivering highly responsive steering with outstanding driver feel."
The addition of a motor-assisted second pinion to the EPS system more precisely assists with turning force and steering assistance, which leads to improved steering feel and feedback for the driver.
Dual-pinion electric power rack and pinion steering system
The NSX features two distinct EPS steering settings: one for the Quiet and Sport modes and one for the Sport+ and Track modes. For the more performance-oriented Sport+ and Track driving modes, an increased level of acuity and performance is accomplished by reducing steering assist based on vehicle speed and steering angle.
Next-Generation Super Sports Brakes
The next-generation electro-mechanical super sports braking system in the NSX delivers powerful and linear stopping performance in combination with highly communicative and easy-to-modulate brake pedal feel and high fade resistance.
The high–performance, Brembo brakes are seamlessly combined with the TMU's regenerative braking capability to support the hybrid battery's state-of-charge and consistent power delivery under demanding driving conditions.
Electro-Servo Braking System
The ESB system has been designed and developed through rigorous testing to provide the driver with superb feedback and brake pedal feel in all conditions, from low-speed city traffic, highway speeds or flat-out track driving.
The high degree of intuitive brake pedal feel is achieved through precise pressure control by the electro-servo brake system. The operation of the ESB is also finely tuned to deliver consistent and predictable brake pedal feel for each of the drive mode settings of the Integrated Dynamic System.
Regenerative Braking
By supplementing the high-performance electro-servo (friction) braking system with regenerative braking, the NSX recycles electricity and feeds it back to the Intelligent Power Unit (IPU). Unlike many such systems, the NSX blends this capability in a seamless and effective way, resulting in intuitive brake pedal feel with superb feedback. Regenerative braking begins as soon as the driver releases the throttle, to maximize IPU recharging during normal driving.
Brake System Components
The high-performance Brembo braking system features:
- Front – Large six-piston calipers with 14.5-in., two-piece, iron and aluminum ventilated brake discs up front
- Rear – Four -piston calipers with 14.0-in., two-piece, iron and aluminum ventilated rotors at the rear
All four calipers are of an aluminum mono block design, which provides even pressure distribution across the surface of the brake disc with outstanding heat dissipation and excellent rigidity. The two-piece iron and aluminum brake discs provide consistent brake pad-to-rotor surface contact with high heat capacity and cooling efficiency, which allows much greater thermal expansion without adverse performance effects.
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An ultra-high-performance carbon ceramic brake disc package (15.0-in. discs up front/14.0-in. rear), available as a factory option, reduces weight. These high-performance brakes save nearly 52 lb. (23.5 kg), when compared to the standard brake package, along with improved fade performance in high-stress conditions, such as extended track sessions. The carbon ceramic rotors are cross-drilled to reduce weight and improve cooling. The package includes a choice of three different brake caliper color options: red, black or silver.
Optimized Brake Cooling
Optimal brake cooling has been achieved as an integral part of the NSX advanced aerodynamic design. Even under the high-stress scenario of extended track sessions, front and rear brake cooling is always robust, providing continued optimum vehicle control.
Typically, effective brake cooling at the rear of a mid-engine vehicle is difficult to achieve due to the surrounding heat from the engine and transmission. Rear brake cooling on the NSX is enhanced by the innovative use of the NSX rear subframe. Two air duct paths have been designed into the hollow subframe. Air passing through the subframe is precisely directed to the rear brakes using specially tuned air deflectors on the rear suspension arms.
Wheels and Tires
The Acura NSX chassis contains a bespoke wheel and tire package that extracts optimal performance from the vehicle in lateral grip, acceleration and braking. Lightweight forged alloy wheels with high lateral stiffness are fitted with high-performance summer tires—Continental ContiSport Contact—to provide the NSX interface with the road. In a joint effort with Continental, the wheel and tire combination was extensively tuned to work in unison with the NSX chassis and Sport Hybrid SH-AWD systems to offer superior traction and grip under both wet and dry conditions. Track-focused ultra‑high‑performance summer tires, with elevated grip levels and even higher response characteristics, are available as dealer-installed options.
The unique "Y" wheel design is a result of the NSX engineering team's extensive research to find the strongest and most rigid spoke structure with the least amount of material. Forged in high-strength aluminum alloy, the wheel design offers a lower total weight than any wheels of similar size and material composition within the NSX competitive class. An optional factory-installed wheel set utilizes a thin, exclusive Interwoven wheel spoke design featuring three options of finish: 3D-machined, polished and painted.
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Both wheel packages feature staggered fitment to optimize chassis performance, the front wheels measuring 19 x 8.5J, with wider 20 x 11J wheels at the rear.
Active Magnetorheological Dampers
Third-generation MR dampers are used at all four corners of the NSX chassis.. These magnetically-controlled dampers help to stabilize the driver and passenger in their seats and stabilize the tire footprint by continuously adjusting damping forces in fractions of a second, instantaneously adapting to the driving situation, driver inputs and road conditions. MR dampers allow the NSX to make optimum use of its high-performance tire design while still providing world-class ride quality.
The reservoir within each MR damper is filled with a special magnetorheological fluid that contains microscopic metallic particles. Running an electric current to each MR damper creates a magnetic field within the fluid that causes an instantaneous change in the fluid properties and resulting change in the damping force.
While other active dampers are limited by their internal valve-based technology to vary the damping force, the Acura MR dampers utilize a unique valve-less design that offers a much broader range of damping force and more rapid responsiveness.
The MR dampers also function as a component of Integrated Dynamics System via two unique damper tuning settings—one biased toward unsprung mass control, used for Quiet and Sport modes; and a second with optimized performance tuning biased toward sprung mass control, used for Sport+ and Track modes.
Power Unit Mounting System
To provide the amount of torque that the new NSX delivers with the least amount of sacrifice to the driver, engineers had to give special consideration to the following when securing the Sport Hybrid SH-AWD power unit to the chassis:
- Supporting the rear power unit's massive torque output with minimal compliance
- Controlling the inertial mass of the power unit during transient driving or road inputs
- Minimizing unwanted power unit vibration to the driver and passenger
The solution was an engine cradle that combines hydraulic (oil-filled) engine mounts with a rigid aluminum subframe plate that supports the engine while acting as a vibration and noise inhibitor.
By employing widely spaced mounting brackets—up high at the front of the engine and a mounting cradle bracket down low at the rear (connected to the 9DCT)—the position of the rear power unit is optimized to greatly reduce roll, pitch and yaw motion of the power unit, providing greater acceleration response and handling ability.
Fuel Tank
Finding the shape and placement of the fuel tank for the best low-weight distribution while providing protection in the event of a rear-end collision was a difficult design challenge. The solution was twin tanks constructed of a specialized resin material. That design permitted tremendous flexibility in the shape of the fuel tanks. The tanks are centrally located behind the rear bulkhead and in front of the engine, which minimizes handling changes with varying fuel levels
Specifications
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Suspension |
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Front Suspension Type |
In-wheel double-wishbone, double lower control arm; aluminum |
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Front Damper Assemblies |
Active Gen III MR coilovers |
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Front Stabilizer Bar |
Hollow steel, 1.04 in. diameter x 0.13 in. wall thickness |
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Rear Suspension Type |
Multi-link; aluminum |
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Rear Dampers |
Active Gen III MR coilovers |
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Rear Stabilizer Bar |
Hollow steel; 0.98 in. diameter x 0.12 in. wall thickness |
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Wheels and Tires |
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Front Wheels |
19x8.5J forged aluminum |
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Front Tires |
245/35ZR19 93Y high-performance summer tires; optional ultimate-handling performance tires |
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Rear Wheels |
20x11J forged aluminum |
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Rear Tires |
305/30ZR20 103Y high-performance summer tires; optional ultimate-handling performance tires |
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Spare Tire |
Tire repair kit |
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Steering |
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Steering Type |
Variable ratio rack and pinion; dual-pinion EPS |
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Steering Wheel Turns, Lock-to-Lock |
1.91 |
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Steering Ratio |
Variable progressive; Range: 12.9:1 (on center) to 11.07:1 |
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Turning Diameter, Curb-to-Curb |
39.7 ft |
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Brake Specifications |
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Front Brake Calipers |
Brembo 6-piston aluminum mono block |
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Front Brake Rotor Type |
Base: 2-Pc floating iron discs w/ aluminum center |
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Front Brake Rotor Size |
Iron: 14.5 in. diameter x 1.3 in. thick |
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Rear Brake Calipers |
Brembo 4-piston aluminum mono block |
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Rear Brake Rotor Type |
Base: 2-Pc floating iron discs with aluminum center |
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Rear Brake Rotor Size |
14.2 in. dia. X 1.3 in. thick (both iron and carbon ceramic) |