MSD 7531 Programmable Digital-7 Plus Installation - Manual

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Parts Included:
1 - Ignition Control, PN 7531
1 - MSD Pro-Data+ CD Rom
4 - Vibration Mounts & Screws
1 - Shielded Cam Sync Harness
1 - 9-Pin Computer Harness
Accessories
Hand Held Monitor, PN 7550
Inductive Cam Sync Pickup Kit, PN 7555
Non-Magnetic Cam Sync Pickup Kit,
PN 2346
Manual Launch RPM Control, PN 7551
Digital Shift Light, PN 7542
MAP Sensor, see page 9
Replacement Harness, PN 8855
Single Pole/Single Throw Relay, PN 8961
Double Pole/Double Throw Relay, PN 8960
WARNING: During installation, disconnect the battery cables. When disconnecting, always remove
the Negative cable first and install it last.
Note: Solid core spark plug wires cannot be used with an MSD Ignition Control.
OPERATION
DIGITAL OPERATION
The MSD Programmable Digital-7 Plus uses a high speed RISC microcontroller to control the ignition’s output
while constantly analyzing the various inputs such as supply voltage, trigger signals and rpm. The high speed
controller can make extremely quick compensations to the output voltage, multiple spark series, timing and rpm
limits while maintaining accurate timing signals to within +/- 0.1° and +/- 10 rpm. The circuits and controller of
the ignition have been thoroughly debounced and suppressed to create protection against Electro Magnetic
Interference (EMI).
CAPACITIVE DISCHARGE
The MSD features a capacitive discharge ignition design. The majority of stock ignition systems are inductive ignitions.
In an inductive ignition, the coil must store energy and step up the supplied voltage to maximum strength between
each firing. At higher rpm, since there is less time to charge the coil to full capacity, the secondary voltage falls short
of reaching its maximum energy level which results in a loss of power or top end miss.
The MSD Ignition features a capacitor which is quickly charged to 520 - 535 volts and stores its energy until the
ignition is triggered. With the CD design, the energy sent to the coil is always at maximum power even at high rpm.
MULTIPLE SPARKS
The MSD produces full power multiple sparks for each firing of a plug. The number of multiple sparks that occur
decreases as rpm increases, however the spark series always lasts for 21° of crankshaft rotation. Above 3,300 rpm
there is simply not enough “time” to fire the spark plug more than once, so there is only one powerful spark.
1 - Mag Pickup Harness, PN 8860
1 - 12-Pin Harness
1 - Coil Harness
1 - Power Lead Harness
Programmable Digital-7 Plus
PN 7531
ONLINE PRODUCT REGISTRATION: Register your MSD product online and you’ll be entered
in our monthly 8.5mm Super Conductor Spark Plug Wire give-away! Registering your product
will help if there is ever a warranty issue with your product and helps the MSD R&D team create
new products that you ask for! Go to www.msdperformance.com/registration.