M&W IGNITIONS Pro-Drag4 User manual

31.10.20.1 © M&W IGNITIONS
Pro-Drag4
160/250mJ S3
ELECTRICAL WIRING
&
OPERATING INSTRUCTIONS
Applicable
S/No’s 35xxxx
FAILURE TO FOLLOW INSTRUCTIONS
WILL VOID WARRANTY
CONTENTS:
2. Installation notes
6. Ignition coil information
7. Connections and specifications
8. 4 Coil sequential ignition
9. Mounting dimensions
Scan to download
current instructions

28.05.18.1 © M&W IGNITIONS 1
INSTALLATION NOTES
(Pro-Drag 250mJ Series 3 systems)
MOUNTING
Do not mount the unit where it will be exposed to water or other
liquids, ensure the bottom condensation slots are unobstructed and
oriented to permit gravity drain. Select a location away from
intense heat and if required provide a source of cooling air.
Failure to use supplied rubber mounts will void warranty!
IGNITION LEADS
Do not use plain metal wire or carbon core ignition leads.
Use spiral wound inductively suppressed metal conductor ignition
leads such as those available from Magnecor www.magnecor.com.
SPARK PLUGS
The use of use non resistor spark plugs (where possible) will greatly
enhance ignition performance.
In some installations the use of resistor spark plugs may be
unavoidable. In these cases ensure they are not damaged by
testing internal resistance value as part of regular maintenance.
Open circuit or high resistance may cause failure of spark plug
wires, ignition coils and CDI.
The use surface discharge or semi surface discharge spark plugs are
limited to naturally aspirated engines.
Keep spark plug gap <= 0.020” (0.5mm) for COP coils and <=
0.025” (0.65mm) for non COP coil high boost applications.
INSULATION PRECAUTIONS
Degrease spark plug insulators, coil/plug boots and installation
tooling to prevent arc tracking or insulation breakdown.
Use (supplied) dielectric grease on spark plug insulators and
coil/plug boots to increase insulation properties and ease

28.05.18.1 © M&W IGNITIONS 2
installation/removal (use of dielectric grease in main connector may
also reduce water ingress).
POWER SUPPLY
Do not use voltage boosters or connect through a PDM.
If wired to a power source shared with the ECU or its sensors erratic
operation may be experienced!
If running a total loss electrical system install a 16V or 18V battery
to ensure supply voltage is maintained above 13V.
WIRING
Wire ignition system directly to battery!
If required wire length exceeds recommendations use paired battery
cable for power and ground to make up distance. Do not rely on
vehicle chassis to provide ground path.
M&W CDI systems are designed to open circuit the external fuse
under conditions of over voltage or reverse polarity. Faults such as
loose battery terminals, poor wiring or defective alternator/regulator
may also cause this to occur.
Use twisted shielded pair wire similar to M27500 for all power/coil
connections. Keep coil wires one continuous length and do not fit an
intermediate connector.
Main connector pins are designed to be roll crimped. Squeeze
crimping or soldering will cause distortion possibly resulting in
misfiring or incorrect CDI operation.
Common coil negative wires must be joined at/inside the connector
(connector pin will correctly crimp a max of 2 * 20ga wires).
Keep coil primary wires well separated from HT leads, coil HV outlet,
coil body and any input wiring!
TRIGGERING
Single box - channels may be triggered in any sequence, twin box –
firing sequence must alternate between boxes (except rotary).
Two box – firing sequence must alternate between boxes.

28.05.18.1 © M&W IGNITIONS 3
250mJ Pro-Drag systems with a trigger edge selection input default
to falling edge ignition. To select rising edge ignition install a
jumper wire between inputs ‘Trigger Edge’ and ‘Edge Ground’ pins.
Where the ECU contains an inbuilt igniter it may be necessary to use
rising edge ignition.
250mJ Pro-Drag systems with a power level switch input are fixed
falling edge ignition.
If CDI trigger edge and ECU ignition edge do not match timing will
be erratic and vary with RPM!
POWER LEVEL SWITCH
To reduce ignition energy under low load conditions some M&W
250mJ units include an (active low) power level switch.
Do not manually activate this feature. Install an adjustable ‘Hobbs’
style manifold pressure switch or use a programmable output from
the ECU to ground the input when engine comes under load.
TUNING
CDI systems are ‘edge triggered’ and not effected by dwell settings!
M&W CDI systems may reduce combustion delay and percentage
misfire requiring a reduction in ignition timing. These changes to
combustion characteristics may also require alterations to fuel flow.
Set ECU ignition delay to zero and tune engine as required.
Always re tune both fuel and timing curves after installing CDI
ignition.
TACHO OUTPUT
The tacho output provides a 50% duty cycle square wave signal
approximately 1V below battery supply voltage. This will work with
most aftermarket digital tacho’s however earlier types and those
designed for coil negative triggering may require a tacho adaptor.
LED INDICATOR
After applying power to switch wire the LED will illuminate, after
approximately 1 second it will extinguish then flash briefly with each
consecutive trigger event.

28.05.18.1 © M&W IGNITIONS 4
A repeated double flash of the LED may indicate a possible faulty
ignition coil, faulty wiring, low supply voltage or damage to the CDI.
TESTING
The CDI may be tested by momentarily grounding the trigger inputs
causing the LED to flash and corresponding ignition coil to spark.
Do not conduct this test without grounded spark plugs installed!
SAFETY
Application of power to ignition system in combination with an
inadvertent ignition event from ECU (powered up/down or engine
rotation) may cause damage to ignition coils, CDI or nearby
personnel.
1. Install grounded metal studs in engine bay and transfer spark
plug ends of HT leads to these between race events or at least when
working on engine.
2. Install aircraft style guarded toggle switch in the CDI ignition
switch wire circuit and disable it at all times except when running
the engine.
Due to extreme energy and voltage levels developed by M&W
ignition systems it is strongly recommended caution be taken to
ensure personnel safety and prevent ignition component damage!
INSTALLATION PRECAUTIONS
Care must be taken due to the propensity for HV flashovers and
insulation breakdown caused by CDI ignitions unique characteristics.
The main cause of CDI damage is conduction of high voltage to coil
primary wiring.
It is essential to fully read and understand these instructions and
have a comprehensive knowledge of automotive electrical systems
before commencing installation.
For further information may be found under the support tab on our
website.

17.07.18.1 © M&W IGNITIONS
IGNITION COILS
(Pro-Drag 250mJ systems)
COIL SELECTION
For ultimate ignition energy use coils specifically designed for CDI
use such as the M&W #COI006. Ignition coils primarily designed for
inductive ignition will significantly limit CDI output.
COP COILS
COP (coil on plug) coils were not designed for the energy levels and
voltage potentials developed by M&W Pro-Drag systems.
Use of COP coils will void warranty
Use at your own risk!
FERRITE CDI COILS
Ferrite core cdi coils provide a lightweight solution for direct fire
applications and give high secondary current however they are not
be suitable for all applications due to their extremely short arc
duration. The high level of EMI emitted by these coils may require
additional shielding to prevent electrical interference.
CAUTION!
Use resistive spark plugs with all COP coils!
Keep spark plug gap <= 0.020” (0.5mm) for COP coils and <=
0.025” (0.65mm) for non COP coil high boost applications.
DO NOT wire ferrite coils in parallel pairs!
DO NOT use ‘Prufex’ brand outboard motor coils or AEM pencil
coils under any circumstances!

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B
ATitle
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Date: 17-Jul-2018 Sheet of
File: D:\M&W\..\Pro-Drag4 250 S3 SW 1.sch Drawn By:
Coil A +
Tacho (T)
Trigger (B)
Coil A & B -
Trigger (A)
Coil C & D -
SPECIFICATIONS
Trigger (C)
Trigger (D)
Coil D +
Ignition switch
Power level (P)
CAUTION!
HIGH VOLTAGE
DISCONNECT POWER BEFORE
WORKING ON UNIT
Ground (Battery)+12V (Battery)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
+12V (Battery) Ground (Battery)
Operating voltage ........................... 12.5V --> 18V DC
Polarity ............................................ Negative ground
Startup voltage ................................ >= 6V
Maximum supply current ............... 15A
Power off current ............................. < 700uA
Maximum ignition frequency .......... 1,000Hz
Energy limit:
Lo power ....................................... 1,000Hz
Hi power ...................................... 700Hz
Coil primary voltage:
Lo power ...................................... 400V
Hi power ...................................... 500V
Spark energy:
Lo power ...................................... 160mJ
Hi power ...................................... 250mJ
Trigger:
Current ......................................... 10mA
Edge .............................................. Falling
Voltage rsisng .............................. >= 3.2V
Voltage falling .............................. <= 1.6V
Tacho output:
Voltage ......................................... Supply - 1.2V
Output current ............................. 100mA
Shape ........................................... Square wave
Operating temperature ................... <= 105°C
Dimensions ..................................... 122L * 110W * 40H
Weight ............................................. 750gm
VIEWED FROM BACK OF CONNECTOR
IGNITIONS
Performance & Quality
W
W
&
Coil C + Coil B +
WAG
11
PRO-DRAG4 160/250mJ S3
17.07.18.1
(C) M&W Ignitions

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Number RevisionSize
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Date: 16-Jun-2023 Sheet of
File: D:\M&W\..\Pro-Drag4 250 S3 SW 2.sch Drawn By:
CAUTION!
HIGH VOLTAGE
DISCONNECT POWER BEFORE
WORKING ON UNIT
123456
7 8 9 101112
13 14 15 16 17 18
BA
WAG
11
4 COIL 160/250mJ SEQUENTIAL
IGNITIONS
Performance & Quality
W
W
&
16.06.23.1
(C) M&W Ignitions
TOP
LOOKING INTO
CONNECTOR ON
BOX
BATTERY
30A FUSE
D
CDI SWITCH
C T
Wire Specifications
POWER SUPPLY:
Use 14ga wire from battery bifurcated into
20ga wire <= 100mm from connector.
Junction is best achieved using a Solistrand
or similar butt splice / barrel crimp.
Maximum recommended wire length is 2M
IGNITION COILS:
Use 20ga wire from cdi to coils and keep as
one continuous length.
Maximum recommended wire length is 2M
* Read istallation guide for
important wiring details!
Coil D Coil B
Coil ACoil C
*
P
Trigger Edge
This unit has fixed falline (negative) edge
trigger
If required rising edge (positive) trigger may
be requested at time of order

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B
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Number RevisionSize
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Date: 17-Jul-2018 Sheet of
File: D:\M&W\..\Mounting dimensions.sch Drawn By:
CAUTION!
HIGH VOLTAGE
DISCONNECT POWER BEFORE
WORKING ON UNIT
99.50 +/- 0.5 MM
120.50 MM131.00 MM
121.50 +/- 0.5 MM
Slot dimensions - 5mm * 10mm
Pro-Drag4
HIGH ENERGY
MICROPROCESSOR CDI
WAG
11
PRO-DRAG4 160/250mJ S3
IGNITIONS
Performance & Quality
W
W
&
17.07.18.1
(C) M&W Ignitions