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Digital Soft-Touch HEI Rev Limiter

PN 8727CT

Parts Included:

1 - Digital HEI Rev Limiter

1 - Wiring Harness

2 - Mounting Screws and Nuts

The Digital HEI Rev Limiter is designed to provide an accurate engine rpm limit for racers using a GM based

HEI (internal coil) Distributor. The rev limit is easy to set with two rotary dials in 100 rpm increments with a

range from 3,000 – 9,900 rpm. The advanced digital technology of the Limiter provides a very accurate and

smooth rev limiting action. The Limiter also has a built-in recall feature that will record the peak rpm recorded

and will display that rpm value for five seconds when the ignition is turned on.

MOUNTING

The Digital Rev Limiter is designed to be mounted in the engine compartment or interior though it should be

mounted away from high heat sources. It is recommended to mount the unit within easy view for the crew

and tech inspectors to easily view the LED display for limit confirmation and adjustments.

Position the unit where the LED and adjustment dials are easy to view and access. Make sure the wiring

harness reaches the distributor and mark the location of the mounting holes. Use a 3/16” bit to drill the holes

and mount the unit with the supplied

hardware.

RPM LIMIT AND SETTINGS

The rpm limit is set using the two rotary

dials on the unit with a range of 3,000-

9,900 rpm in 100 rpm increments. The left

dial controls the 1,000s and the right dial

controls the 100s of the desired rpm value

(Figure 1). There are small numbers on

the dials to show the rpm value however

the LED will display the rpm value being

set when the ignition is in the On position

(engine can be running or not)

Maximum RPM Recorded: The PN 8727CT records the maximum rpm value that the engine reached in the

last 20 minutes of power on. When the ignition is turned on, the max rpm will flash on the display for

the first five seconds before reverting to the set rpm limit.

To reset the maximum rpm value, power to the PN 8727CT must remain on for 20 consecutive

minutes.

Faults: The Digital Rev Limiter will record and display an ‘F’ to show a Fault occurred to alert of a wiring or

operation discrpency. The ‘F’ will display on the LED screen for three seconds after the Max RPM is

shown at ignition on. Also, a flashing decimal point to the right of the LED read out to alert when a

Fault has been recorded. An ‘F’ will be recorded when the Green wire is disconnected or opened

with the engine running above 2000 rpm.

WARNING: Before installing the Digital Soft-Touch HEI Rev Limiter, disconnect the battery cables. When

disconnecting the battery cables, always remove the Negative (-) cable first and install it last.

Figure 1 The Digital HEI Rev Limiter.

6 5 0 0

.

2 3

2 3

1000s

ADJUSTMENT

100s

ADJUSTMENT

FAULT

INDICATOR

GREEN

RED

BLACK