MSD 8225 Installation

MSD GM HEI Coil

PN 8225

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Parts Included:

1 - MSD Coil, PN 8225
1 - 4" Black Ground Wire
1 - Rubber Isolator

The MSD HEI Coil is designed for use with the MSD High Output HEI Module, PN 8364. It will work
with stock ignition modules but for maximum output use the MSD HEI Module.

Note: The Rotor Bushing supplied is a replacement unit designed for stock or mild HEI Distributors

and has very high resistance. If an MSD 7 Series or Digital Series Ignition is used an MSD Low
Resistance Rotor Bushing, PN 8412, must be used to prevent damage to the cap and rotor.

Disassembly

1. Remove the dust cover to access the HEI Coil and
disconnect the three wiring harnesses from the
distributor cap.

2. Remove the four screws that hold the original coil.

3. Lift the coil out of the cap and discard the original
rubber isolator and rotor bushing.

1 - Rotor Bushing
4 - Mounting Screws

Installation

1. Install the new rotor bushing and rubber isolator.

2. Install the MSD Coil. The terminals should slide
easily into position into the cap. The Yellow and
Red leads go in the outer slots of the cap. They
cannot be interchanged.

3. Insert the Black ground wire in the center slot of
the cap and connect it to one of the Coil’s retaining
screws (Figure 2).

4. Install the other three retaining screws followed by
the dust cover and connect the harnesses.

MSD also offers the following parts to upgrade and
maintain your GM HEI Distributor:

PN 8411 Heavy Duty Cap, Red
PN 8410 Rotor
PN 8402 Factory Style Dust Cover
PN 8412 Low Resistance Rotor Bushing
PN 83645 High Output Ignition Module
PN 8401 Modified Dust Cover for External Coil

Figure 1 Installing the MSD GM HEI Coil.

M S D   •   W W W . M S D P E R F O R M A N C E . C O M   •   ( 9 1 5 )   8 5 7 - 5 2 0 0   •   F A X   ( 9 1 5 )   8 5 7 -3 3 4 4

Figure 2 Wire Location.

Service

In case of malfunction, this MSD component will be repaired free of charge according to the terms of the warranty.

When returning MSD components for warranty service, Proof of Purchase must be supplied for verification. After
the warranty period has expired, repair service is based on a minimum and maximum fee.

All returns must have a Return Material Authorization (RMA) number issued to them before

being returned. To obtain an RMA number please contact MSD Customer Service at 1 (888) MSD-7859 or visit
our website at www.msdperformance.com/rma to automatically obtain a number and shipping information.

When returning the unit for repair, leave all wires at the length in which you have them installed. Be sure to include
a detailed account of any problems experienced, and what components and accessories are installed on the vehicle.
The repaired unit will be returned as soon as possible using Ground shipping methods (ground shipping is covered
by warranty). For more information, call MSD at [phone]. MSD technicians are available from 7:00 a.m. to
5:00 p.m. Monday - Friday (mountain time).

Limited Warranty

M

SD warrants this product to be free from defects in material and workmanship under its intended normal use*,
when properly installed and purchased from an authorized MSD dealer, for a period of one year from the date of
the original purchase. This warranty is void for any products purchased through auction websites. If found to be
defective as mentioned above, it will be repaired or replaced at the option of MSD. Any item that is covered under
this warranty will be returned free of charge using Ground shipping methods.
This shall constitute the sole remedy of the purchaser and the sole liability of MSD. To the extent permitted by
law, the foregoing is exclusive and in lieu of all other warranties or representation whether expressed or implied,
including any implied warranty of merchantability or fitness. In no event shall MSD or its suppliers be liable for special
or consequential damages.
*Intended normal use means that this item is being used as was originally intended and for the original application
as sold by MSD. Any modifications to this item or if it is used on an application other than what MSD markets the
product, the warranty will be void. It is the sole responsibility of the customer to determine that this item will work for
the application they are intending. MSD will accept no liability for custom applications.

M S D   •   W W W . M S D P E R F O R M A N C E . C O M   •   ( 9 1 5 )   8 5 7 - 5 2 0 0   •   F A X   ( 9 1 5 )   8 5 7 -3 3 4 4

© 2012 Autotr onic Con trols Corporat ion

FRM29079 Revised 12/11 Printed in U.S.A.