MSD 7562 Programmable Launch Boost Controller Installation - Manual (Page 10)

10 INSTALLATION INSTRUCTIONS
MSD IGNITION • 1490 HENRY BRENNAN DR., EL PASO, TEXAS 79936 • (915) 857-5200 • FAX (915) 857-3344
SETTING MINIMUM BOOST
If you are using C
O
2 to control both sides of the wastegate actuator, you can skip this step. A
minimum boost pressure must be set in the Controller. To find this, you need to bring the engine
into boost conditions while the MSD Controller is disconnected from the solenoid valve (the 4-pin
connector) and the waste gate ports on the spring side are open. It is recommended to use the
record function of the Controller to help obtain a minimum boost pressure. With the PC to the
Controller open the MSD Graphview Software. Disconnect the solenoid valve connector(s) and
start the engine. Cycle the Light Blue and Dark Blue wires to begin the recording sequence and
bring the engine into boost pressure.
Once this procedure is done, the test record should be visible in the Launch History window. Click
on View, then select Trace Box followed by the Tier button. This will display the data traces in full
screen format in the History Trace box and you can find the minimum boost pressure. For example
if the record shows that the boost came up to 10psg (or 23psia with an atmospheric pressure
reference of 13psia), then the minimum controlled boost would be greater than 10psi boost. It is
recommended to use the lightest spring for the desired minimum boost that is to be programmed
and controlled.
Now that the minimum boost pressure is known, we can program a target pressure to be controlled.
For example if the minimum was measured at 10psi boost then set the BurnBoost to 11psi plus the
atmospheric reference pressure measured. In our example we saw that the atmospheric pressure
was 13psia. To develop 11psi of boost, add the desired pressure to the atmospheric value to program
the boost pressure in psia units, 11+13=24psia. Now also set the Boost Pressure Curve to this
same value 24psia.
Next, set the PID defaults for P=40, I=0, and D=40. This allows tuning the PID without any I term to
begin with. (These values were near optimum based on a Buick Grand National turbo testing.) At
this point, connect the 4-pin connector from Controller to the solenoid valves. (The valves will not
be powered on until the engine is running, by sensing the tachometer signal.) With the PC connected
and the power On, Graphview will display the monitor items. The RefPsia is the current atmospheric
pressure taken from the MAP sensor that is used to measure the manifold boost pressure. The
PWM should be displaying a value between 40 and 100, typically if you have programmed the
boost pressure correctly. If the PWM value stays above 100 then the pressure you have programmed
is at or below the atmospheric pressure and must be corrected before proceeding. Looking at the
TargetPsi value, it should be greater than the RefPsia or MapPsia values.
Before making the next boost test, verify that the TargetPsi value is the correct value for the minimum
controlled boost. Reset the Controller by cycling the Light Blue wire activated and have the Dark
Blue launch wire activated. Do not deactivate the Launch wire until the engine is ready to make
boost! Once ready, release the Launch wire to begin the record function. Build boost for at least 5-
6 seconds or until the boost is steady. The LaunMode monitor item will display
PRE while the
launch wire is at +12 volts then change to
RUN when it begins recording.
After making a boost run, transfer and save the data in the Launch History window. Evaluate the
data and make changes to the PID values if needed for optimum controller response and pressure
regulation. Following are several test plots and information.