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/InstallationPower Window Main Switch Removal/Installation
1. Disconnect the negative battery cable..
2. Remove the cover A.
3. Insert a tape-wrapped fastener remover shown in the figure and remove the
tab B in the direction of arrow (1).
4. Slide the power window main switch cover in the direction of the arrow (2)
shown in the figure and ...
Oil Seal (Differential) Replacement [C66 M R]
1. Remove the front under cover No.2..
2. Drain the manual transaxle oil..
3. Disconnect the drive shaft (LH) from the MTX..
4. Disconnect the drive shaft (RH) from the MTX..
5. Remove the oil seal (LH).
6. Remove the oil seal (RH).
7. Using the SSTs and a hammer, tap a new oil s ...
Transmission/Transaxle Features
Clutch and Manual Transaxle [C66M-R]
A newly developed, C6-type manual transaxle (SKYACTIV-MT) with 6 forward
gears and 1 reverse gear has been adopted.
Automatic Transaxle [FW6A-EL, FW6AX-EL]
A newly developed, FW6A(X)-EL-type electronically controlled automatic transaxle
...