Acura believes the best way to engineer a feeling, to become one with the car, is the idea of zero-delay. Basically any inputs from the driver must result in immediate outputs from the car. For example, all of the interfaces that you as a driver touch, must react seamlessly. The throttle, the brakes, the steering, and the shifting. If there’s a delay between when you act, and when the car reacts, you feel disconnected from the driving experience, and it’s that delay that Acura sought to eliminate.
Typically with turbocharged engines, there’s a response delay in the throttle as a result of turbo lag. In the NSX, this delay is eliminated by using the immediate torque of the three electric motors. All three motors provide peak torque up to 2,000 RPM, and by 2,000 RPM the engine is ready to provide peak torque all the way to 6,000 RPM. The result is an instantaneous response to your throttle inputs, and a huge range of available torque regardless of the engine speed.
For the steering, the NSX uses an electronically assisted power steering rack with a variable ratio which gets progressively tighter as you turn the wheel. The ratio starts at 12.9, so you have quick turn in without much steering angle. But having a car that’s instantly responsive to your steering inputs isn’t just about the steering ratio.
With the mid-engine design, the vehicles mass is located towards the center, and this reduces the polar moment of inertia, allowing for the NSX to change directions more quickly. The body of car is a multi-material space frame that’s extremely rigid, so whenever steering input is asked for, it’s immediately answered.
On top of the rigid body and steering system, Acura also uses direct yaw control. Acura’s agile handling assist can brake the inside tires when turning into a corner to help prevent understeer, or brake the outside tires to help prevent oversteer. Simultaneously, the twin motor unit can provide negative torque to the inside tire in a corner to create a yaw moment, as well as accelerate the outside motor to help pull the car out of a corner. The motors can act independently of throttle control, meaning the twin motor unit can can send power instantly to the outside wheel as soon as the driver turns into a corner, as needed through the corner, and then at the throttle application point to help pull the car out of a corner and keep it on path. All of this tech is seamlessly combined to give the driver an instantaneous response to their steering inputs, and a car that follows the intended steering path.
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