Some cars accelerate smoothly with just a slight touch of the accelerator pedal.
On the other hand, some cars feel like they take a breath before accelerating after you press the pedal.
Even if the horsepower listed in the catalog isn't that different, the "speed" and "lightness" you feel when driving can vary greatly.
"Throttle response" is crucial when considering this difference.
Throttle response isn't simply determined by engine horsepower alone. Multiple factors are involved, including the accelerator pedal, electronic control, engine, turbo, transmission, and drivetrain.
This article will explain what throttle response is, why some cars feel slow to react, and how the "instantaneous acceleration" sensation is created, in an easy-to-understand manner.
What is Throttle Response?
Throttle response, simply put, is "how quickly a car reacts to accelerator input."
For example, imagine you're driving at 40 km/h and you press the accelerator further.
If the car moves forward at that instant, you'll likely feel that the "throttle response is good" or "the reaction is sharp."
Conversely, if there's a slight delay after you press the accelerator before the engine RPM increases and acceleration begins, you might feel that the "throttle response is poor" or "there's a one-beat delay."
It's important to note here that throttle response and maximum output are distinct concepts.
Even cars with high maximum output can have a gentle response, while cars with less maximum output but quick reactions to accelerator input can feel very nimble in city driving.
What happens inside the car the moment you press the accelerator?
Many older cars used mechanical connections, such as wires, between the accelerator pedal and the throttle valve.
Today, cars generally use electronically controlled throttles.
When the driver presses the accelerator, a sensor detects the amount of input.
The ECU receives this information and determines the required throttle opening and torque, taking into account the engine's condition and vehicle control parameters.