Purpose, Function
By lengthening the exhaust passage, the transmission of exhaust pressure waves to other cylinders can be delayed, and the amount of gas exhausted from a cylinder and forced back inside the combustion chamber is reduced By reducing the residual gas, the temperature inside the combustion chamber is reduced and the occurrence of knocking even at a high compression ratio is inhibited.
Construction
The exhaust manifold is installed to the rear of the engine. In addition, the catalytic converter (WU-TWC) is integrated (WU-TWC).

When the No.1 cylinder is at the intake stroke, the No.3 cylinder is at the exhaust stroke. By inducing the high temperature gas exhausted from the No.3 cylinder into the No.1 cylinder, the high temperature gas in the No.1 cylinder remains. If the amount of residual gas is high, the temperature in the combustion chamber rises and knocking can easily occur. With the 4-2-1 exhaust system, the transmission of exhaust pressure waves between each cylinder is delayed by the long exhaust pipes.

Exhaust System Removal/InstallationEngine Mount Disassembly/Assembly
No.1 Engine Mount (2WD)
1. Remove the front under cover No.2..
2. Remove in the order indicated in the table.
3. Install in the reverse order of removal.
1
No.1 engine mount rubber
(See No.1 engine mount rubber removal note (2WD).)
(See No.1 engine mount inst ...
Driveline/Axle Features
Improved driveability
Bell-shaped constant velocity joint adopted for wheel-side joint
of front and rear drive shaft
Tripod-shaped constant velocity joint adopted for differential-side
joint of front drive shaft (ATX) and rear drive shaft
...
Airflow Mode Main Link Removal/Installation
Full-auto Air Conditioner
1. The airflow mode main link is installed to the airflow mode actuator. When
removing the airflow mode main link, refer to the airflow mode actuator removal/installation..
Manual Air Conditioner
1. Disconnect the negative battery cable..
2. Remove the glove compar ...