MSD 8655 Installation

Universal Flying Magnet Crank Trigger Kit

Parts Included:

1 – Trigger Wheel, 7.25” Diameter 1 – Pickup Holder Base
1 – Universal Pickup Holder 1 – Non-Magnetic Pickup, PN 8276
1 – Universal Bracket 2 – Bolts, 5/16 – 24 x 1.25”
2 – Washers, 5/16” 6 – Matched Magnets and Rivets

Note: This Kit requires fabrication for your specific application. It is recommended to use a

professional machine shop.

TRIGGER WHEEL

The Trigger Wheel is 3/8” thick
aluminum, has a 7.25” diameter
and a 1” hole in the center. It has
magnet positions machined for
up to 12-cylinder applications (six
magnets). Figure 1 shows where
each magnet needs to be installed
depending on the number of
cylinders.

PN 8655

The Wheel retaining holes must
be machined, as well as a
centering method. It is imperative
that the wheel be centered
accurately.

Figure 1 Magnet Location for Different Engine Applications.

AUTOTRONIC CONTROLS CORPORATION • 1490 HENRY BRENNAN DR., EL PASO, TEXAS 79936 • [phone] • FAX [phone]

2 INSTALLATION INSTRUCTIONS

MAGNET INSTALLATION

The magnets that are supplied are a
matched set and must be installed in one
position to produce the correct trigger
signal.

1. Determine which side of the wheel will
face out. Mark this position.

2. Install the magnet in the wheel with the
hole in the plastic overmolding facing
out from the engine (Figure 2). The
chamfer on the magnet must be
positioned next to the aluminum rivet.

3. Install the rivet. It must be set by using a
press or vice with a set of smooth,
parallel jaws (such as the vice on a
milling machine).

BRACKET AND PICKUP MOUNT

Figure 2 Installing the Magnets.

Once the Trigger Wheel mounting is complete, the brackets need to be created. The mounting
bracket can be cut and machined to meet your requirements. Consider these tips when machining
the bracket:

It is required to have at least two retaining bolts to secure the bracket.
Do not mount the bracket flush to the block. It will be necessary to be able to install the pickup

holder bolt retainer behind the bracket.

The pickup must be spaced 5/8” away from the trigger wheel (Figure 3). This is required so the

air gap between the pickup and trigger wheel will remain constant through its adjustment range.

Figure 3 Pickup Bracket Placement.

AUTOTRONIC CONTROLS CORPORATION • 1490 HENRY BRENNAN DR., EL PASO, TEXAS 79936 • [phone] • FAX [phone]