Mallory Ignition Mallory HYFIRE IV SERIES Ignition System 692_697 - Manual (Page 11)

11
RPM LIMITER OPERATION
HYFIRE ® IVC Ignition System Part No. 692 only
The HYFIRE ® IVC Ignition System has a microcomputer controlled RPM limiting system. The RPM
limiting system has an engine protection RPM limiter and a staging control RPM limiter. The staging
control RPM limiter is triggered by applying 12 volts to the ORANGE WIRE. Connect the ORANGE
WIRE to 12-volt/line-lock, trans-brake or manual/toggle switches.
The RPM limiters are adjustable from 1,000 to 12,000 RPM in increments of 100 RPM. The
engine protection RPM limiter is factory set at 4,000 RPM.
NOTE:The engine protection RPM limiter must be set between 1,000 and 12,000 RPM. Any
other RPM setting outside the adjustment range stops the ignition system from operating.
The ignition system will resume operation once the engine protection RPM limiter is set
properly between 1,000 and 12,000 RPM.
If you are not going to use the engine protection RPM limiter, set the RPM value higher than
your engine will normally run (up to 12,000 RPM). Similarly, if you are not going to use the
staging control RPM limiter, avoid applying 12 volts to the ORANGE WIRE.
The RPM limiter switches for setting the RPM limiters are under the slide-back cover on top
of the housing. Loosen the four screws and slide the cover to see the RPM limiter switches.
You will see two sets of RPM limiter switches. One set of switches is marked “HIGH SIDE”.
These are the engine protection RPM limiter switches. One set of switches is marked
“STAGE”. These are the staging control set of RPM limiter switches. Between the two
switches is a number indicator. It has markings of “1000” and “100” along with markings of
“8, 4, 2 and 1.” Switches of each limiter are set ON to add combinations of 1, 2, 4 and 8 of
each switches’ hundred and thousand sections. Notice that the switches are marked “ON” in
their corner.
EXAMPLE: If you want to set the engine protection at 7,300 RPM, set the HIGH SIDE
switches’ thousand section to 8-off, 4-ON, 2-ON and 1-ON (4+2+1=7 thousand). Similarly,
set the HIGH SIDE switches’ hundred section to 8-off, 4-off, 2-ON and 1-ON (2+1=3
hundred). As stated earlier, if you are not going to use the engine protection RPM limiter, set
the RPM value higher than your engine will normally run (up to 12,000 RPM).
EXAMPLE: If you want to set the staging control at 5,600 RPM, set the STAGE switches’
thousand section to 8-off, 4-ON, 2-off and 1-ON (4+1=5 thousand). Similarly, set the STAGE
switches’ hundred section to 8-off, 4-ON, 2-ON and 1-off (4+2=6 hundred). The staging
control RPM limiter is triggered by applying 12 volts to the ORANGE WIRE. Connect the
ORANGE WIRE to 12-volt/line-lock, trans-brake wire or manual/toggle switches.
NOTE: The RPM limiting systems will not work properly with odd-fire V6 applications. The
RPM limiting systems are not recommended as an engine speed governor. Similarly, forcing
engine RPM past the RPM limiter continuously for long intervals can cause problems
resulting from fuel build up in the exhaust system that may adversely affect exhaust oxygen
sensors (if used) and cause severe backfiring.
STAGE
ON
HIGH SIDE
ON
ADD FOR
T
O
T
AL RPM
ADD FOR
T
O
T
AL RPM
8000
4000
2000
1000
800
400
200
100
ON ON
STAGING
RPM
EXAMPLE:
5,600 RPM ENGINE
PROTECTION
RPM
EXAMPLE:
7,300 RPM
OPTIONAL IGNITION ACCESSORIES
Single Stage High Speed Retard – Part No. 618-1
Mallory’s Single Stage High Speed Retard is a finger tip adjustable ignition timing retard
control. The adjustment knob provides full adjustment range of 0°-15°. This retard is designed
with matching mating plugs so it can to be added between the HYFIRE ® IV Electronic Ignition
Control and the Ignition Control Harness.
Multi Stage High Speed Retard – Part No. 618-3
This is a finger tip adjustable 3-stage timing retard control with an adjustment range for the first
and second stage of 0°-15° and a range of 0°- 20° for the third stage. Each succeeding stage
overrides the previous stage to allow you to reduce (or add) ignition timing on a succeeding
stage. This retard is designed with matching mating plugs so it can to be added between the
HYFIRE ® IV Electronic Ignition Control and the Ignition Control Harness.
Mallory Electronic Advance Computer – Part Nos. 600-04, 600-06 and 600-08
This is a user programmable advance curve system using a CMOS microprocessor for
advance calculations. This allows you to select from 256 different advance curve combinations!
It is designed with matching mating plugs so it can to be added between the HYFIRE ® IV
Electronic Ignition Control and the Ignition Control Harness.
Mallory Remote Timing Control – Part No. 631
Mallory’s Remote Timing Control allows you to change the ignition timing as you drive for
maximum performance, for better fuel economy or to avoid engine knock.
NOTE: The accessories listed above will not work properly with odd-fire V6
applications or point trigger distributors. They are not designed for marine use.
Mallory RPM Activated Switch – Part No. 627A
This device is programmable from 3,000-10,800 RPM in increments of 100 RPM. It features
integral 5 amp relay contacts to operate 12-volt or ground circuits with connections for normally
open and normally closed operation. It works with any 8, 6 (includes odd-fire, semi-even fire,
and even-fire V6 engines), or 4 cylinder application and triggers from the tach output terminal
on the HYFIRE ® IV Electronic Ignition Control.
Mallory Fuel Injection and Tachometer Adapter – Part No. 29074 and 29078
Some applications with fuel injection or a tachometer need a voltage spike signal from the
negative side of the coil before they will operate properly. This signal changes once the
HYFIRE ® IV Electronic Ignition Control is installed. Mallory’s adapter provides the proper
signal to trigger most fuel injection systems and voltage/current triggered tachometers.
FIGURE 19