2008 MITSUBISHI LANCER EVOLUTION X Spark

GENERAL DESCRIPTION
ENGINE MECHANICAL11A-2
GENERAL DESCRIPTIONM2112000101162
This model is equipped with a newly developed 4B11
engine. It is a 4-cylinder, double overhead camshaft
(DOHC) engine with a 2.0-L cylinder displacement.
This engine has adopted the following features:
•MIVEC (MITSUBISHI INNOVATIVE VALVE TIM-
ING ELECTRONIC CONTROL SYSTEM) for
both the intake and exhaust valves
•Cylinder block made of an aluminum alloy
•Valve train with direct-acting valve tappets
•Silent timing chain
MAIN SPECIFICATIONS
DescriptionsSpecifications
Engine type4B11
Bore × stroke mm (in)86 (3.4) × 86 (3.4)
Total displacement cm3 (cu in)1,998 (121.9)
Combustion chamberPent-roof type
Number of cylinders4
Valve mechanismTy p eDOHC
Intake valve8
Exhaust valve8
Compression ratio10.0
Va l v e t i m i n gIntake valveOpens (BTDC)3° − 28°
0° − 25°
Closes (ABDC)45° − 20°
48° − 23°
Exhaust valveOpens (BBDC)41° − 21°
44° − 24°
Closes (ATDC)3° − 23°
0° − 20°
Maximum output kW/r/min (HP/r/min)107/6,000 (143/6,000)
113/6,000 (152/6,000)
Maximum torque N⋅m/r/min (lbs-ft/r/min)194/4,250 (143/4,250)
198/4,250 (146/4,250)
Fuel injection system typeElectronic control MPI
Ignition system typeElectronic spark-advance control type (4-coil
type)
Generator typeAlternating current system (with built-in IC
regulator)
Starter motor typeReduction drive type

BASE ENGINE
ENGINE MECHANICAL11A-3
BASE ENGINEM2112001001050
CYLINDER HEAD
A cylinder head made of an aluminum alloy, which is
lightweight and offers a high level of cooling effi
-
ciency, has been adopted. A pentroof combustion
chamber with a center spark plug has been adopted.
It has a small valve compound angle to realize a
compact chamber.
Cross-flow type intake and exhaust ports have been
adopted. Two intake ports and two exhaust ports are
provided independently on the right and left sides.
Five camshaft bearings are provided at the intake
and exhaust sides, respectively. The No. 4 bearing
sustains the thrust load of the camshaft. Only the No.
1 bearing uses a bearing cap that integrates both the
intake and exhaust sides.
VA LV E S E AT S
Sintered alloy valve seats have been adopted.The oversized (0.3 mm) service parts are available.
VA LV E G U I D E S
Valve guides that are common to both the intake and
exhaust have been adopted.The oversized (0.25 mm) service parts are available.
AK502483
Valve guide
AD
Exhaust side
Intake side

16-1
GROUP 16
ENGINE
ELECTRICAL
CONTENTS
STARTER MOTOR . . . . . . . . . . . . . .16-2
ALTERNATOR . . . . . . . . . . . . . . . . . .16-2
IGNITION COIL . . . . . . . . . . . . . . . . . .16-2
SPARK PLUG . . . . . . . . . . . . . . . . . . .16-3

SPARK PLUG
ENGINE ELECTRICAL16-3
SPARK PLUGM2163005000068
Iridium-tipped spark plugs are used.
AK604562AB
Iridium

IGNITION TIMING AND CONTROL FOR CURRENT CARRYING TIME
MULTIPORT FUEL SYSTEM (MFI)13A-35
IGNITION TIMING AND CONTROL FOR CURRENT
CARRYING TIME
M2132027100089
Ignition timing is pre-set according to engine driving
conditions. Compensations are made according to
pre-set values depending on conditions such as
engine coolant temperature, battery voltage etc. to
decide optimum ignition timing. Primary current con
-
nect/disconnect signal is sent to the power transistor
to control ignition timing. Ignition is done in sequence
of cylinders 1, 3, 4, 2.
System Configuration Diagram
AK502722AD
ECM MFI relay
Spark plugs Ignition
coils
Cylinder No. 1 2 3 4Battery
Mass airflow sensor
Intake air temperature sensor
Manifold absolute
pressure sensor
Engine coolant
temperature sensor
Intake camshaft position sensor
Exhaust camshaft position sensor
Crankshaft position sensor
Knock sensor
Ignition switch-ST Throttle position sensor

IGNITION TIMING AND CONTROL FOR CURRENT CARRYING TIME
MULTIPORT FUEL SYSTEM (MFI)13A-37
2. Spark-advance control and current carrying
time control
.
[During start]
ECM initiates ignition at fixed ignition timing (5° BTDC) syn-
chronized with the crankshaft position sensor signal.
.
[During normal operation]
After determining the basic spark-advance based on the intake
air volume and engine speed, ECM makes compensations
based on input from various sensors to control the optimum
spark-advance and current carrying time.
List of main compensations for spark-advance control and current carrying time control
.
[Control for checking ignition timing]
During basic ignition timing set mode for M.U.T.-III actuator test
function, sparking is done with fixed ignition timing (5
° BTDC)
synchronized with crankshaft position sensor signal.
CompensationsContent
Intake air temperature compensationCompensation is made according to intake air
temperature. The higher the intake air temperature
the greater the delay in ignition timing.
Engine coolant temperature compensationCompensation is made according to engine coolant
temperature. The lower the engine coolant
temperature the greater the advance in ignition
timing.
Knocking compensationCompensation is made according to generation of
knocking. The greater the knocking the greater the
delay in ignition timing.
Stable idle compensationCompensation is made according to change in idle
speed. In case engine speed becomes lower than
target speed, ignition timing is advanced.
Delay compensation when changing shiftDuring change of shift, sparking is delayed
compared to normal ignition timing to reduce
engine output torque and absorb the shock of the
shift change.
Battery voltage compensationCompensation is made depending on battery
voltage. The lower the battery voltage the greater
the current carrying time and when battery voltage
is high current carrying time is shortened.