These are the exhaust sounds heard in modern cars, especially performance and sports cars. These sounds are popping and hissing sounds coming from the exhaust when the engine is idled or when you take your foot off the gas. These sounds, often called "pop and bang" or "burbles", are achieved through modifications to the vehicle's engine control unit (ECU) software.
These sounds occur due to fuel combustion and explosions in the exhaust system. It is especially heard when you take your foot off the gas pedal or when the engine is idling.
When you take your foot off the accelerator pedal, the engine control unit (ECU) reduces the amount of fuel sent to the cylinders, but does not cut it off completely. This small amount of fuel continues to burn in the exhaust system and explosion sounds are produced.
The most common method is to modify the software of the vehicle's ECU. This allows extra fuel to be injected under certain conditions during engine operation and to burn this fuel in the exhaust system.
Ignition timing also plays an important role in creating pop and bang sounds. By delaying the ignition timing, unburned fuel is allowed to reach the exhaust system and explosions occur there.
In some cases, changes to exhaust system components (for example, mufflers or resonators) also contribute to these sounds.
Constant explosions and high heat can cause wear and damage to the exhaust system and engine components. In particular, components such as exhaust valves and catalytic converters may be damaged.
Pop and bang modifications can increase fuel consumption. Using extra fuel during combustion negatively affects overall fuel economy.
Such sounds can be disturbing to surrounding people and neighbors. Additionally, in some areas, vehicles that make excessive noise may be regulated and fined.
