MSD Top Ten Ignition Questions Tech Bulletin - Manual

MSD’s Tech Bulletins are designed to give you a more in-depth
understanding of the ignition system and its components. If you have any other questions about the
subject or MSD products you can contact our Customer Support Department at (915) 855-7123 or
email your questions to [email protected].
Top Ten Ignition Questions
MSD’s Customer Support Department receives numbers of calls and e-mails everyday from racers and enthusiasts
seeking recommendations or ways to tweak out another tenth of performance. To help you learn more about ignitions, they
all got together and came up with this list of the top ten questions they receive.
If your top question isn’t included in this list, call our Customer Support Team at (915) 855-7123 or e-mail us at msdtech@
msdignition.com. Our techs are ready and able to answer all of your questions!
1. What’s the differences between a Capacitive Discharge (CD) igni-
tion like an MSD and my stock ignition system?
The biggest difference is that the majority of stock ignitions
are inductive ignitions. Inductive ignition systems are used
due to their simplicity and inexpensive production. For stock
applications these ignitions are adequate, but when it comes
to gaining performance, factory inductive ignitions fall short.
The primary weak link of a stock ignition is because the coil
serves double duty. The coil must act as a step-up transformer
to create a higher voltage spark, plus it needs to store this
power until the ignition is triggered. As engine rpm increases
there isn’t enough time to completely step-up the voltage
before the ignition is triggered resulting in a weaker spark.
This low voltage spark may not be enough to light the fuel
mixture in the cylinder which will result in a misfire and loss
of power.
A CD ignition, like an MSD 6 Series, is capable of producing
full power sparks throughout the entire rpm range. It draws
its energy directly from the battery where a custom wound
transformer steps it up to over 460 volts. This voltage is then
stored in a capacitor until the ignition is triggered. At this point,
all of the voltage is dumped into the coil where it is transformed
into even more voltage, anywhere from 30,000 - 45,000 volts
depending on the coil, which is sent to the distributor and
finally to the plugs.
The ability to produce high power sparks throughout the
entire rpm range of your engine is why you need a CD ignition. The payoff is complete combustion of the fuel mix-
ture which results in more power, increased throttle response, a smooth idle, quick starts, improved economy and
reduced plug fouling.
All engines will benefit from a CD ignition but when you’re planning on engine modifications, the need for an MSD
Ignition increases. In particular, if you’re planning these types of engine modifications, you should be installing a CD
ignition:
• Improving air flow into the engine or richening the fuel mixture (rejetting or larger injectors)
• Adding a super/turbocharger or a nitrous oxide system
• Increasing the compression ratio and consistent high rpm operation
2. Why does an MSD produce multiple sparks and what are the benefits?
Conventional CD ignitions supply one spark of intense energy but for a short duration (time). An MSD uses mul-
tiple sparking technology to take advantage of the quick rise time and power of a CD Ignition by producing a series
of sparks. More sparks equal more heat in the combustion chamber resulting in complete combustion of the fuel
mixture which produces more power. At lower rpm, there are many benefits to multiple sparks including a smooth
Other steps to avoid EMI problems include routing your coil’s primary wires away from other plug wires. The mag-
netic pickup harness coming from the distributor or crank trigger should be routed away from other wires and is a
good idea to have it mounted along a metal surface that will act as a ground plain. MSD also offers a six feet long
shielded mag pickup cable, PN 8862, that can be used if you are having problems with EMI interfering with other
electronics on your vehicle.
9. How can I test an MSD ignition to see if it is working?
Checking for spark output of your MSD is easy. Following is a simple procedure for testing your MSD for spark.
1. Turn the ignition switch “OFF”.
2. Remove the coil wire from the distributor cap and place it 1/2” from ground. DO NOT CRANK OVER THE ENGINE. When
you continue with this test, a high voltage spark will jump this 1/2” gap so make sure there is no fuel or flammable
mixtures near the plug wire end.
3. If triggering with the Magnetic Pickup (Green and Violet):
A. Disconnect the magnetic trigger wires from the MSD. Turn the Ignition Switch “On”. DO NOT CRANK OVER
THE ENGINE.
B. Use a paper clip or jumper wire to short the Green and Violet wires going to the MSD together several times. A
spark should jump the gap every time the wires are shorted.
4. If triggering with the White wire (points/amplifier):
A. Disconnect the White wire of the MSD from the
distributor trigger or ignition amplifier. Turn the
Ignition Switch “On”. DO NOT CRANK OVER
THE ENGINE.
B. Tap the White MSD wire to ground several
times. A spark should jump the gap as you do
this.
5. If there is no spark, substitute another ignition coil
and repeat the test. If there is now spark, the coil is
at fault. If there is still no spark it is possible that the
MSD Ignition needs to be serviced. If the warranty
period is over, MSD offers repairs at nominal fees.
For more information on repair services, contact our
Customer Support Department at (915) 855-7123
or [email protected]
10. Why should I purchase MSD
products over another manu-
facturer?
In the last few years a lot of other “performance”
ignition companies have cropped up and not surpris-
ingly, their ignitions are all similar to an MSD. They’re
capacitive discharge, multiple sparking designs
with rev limiters and timing controls. MSD was the
first ignition company to use capacitive discharge,
multiple sparking technology. We were the first to
offer rev limiters, billet distributors and crank triggers. We know what it takes to deliver ignition performance and reli-
ability. These are things you only learn with experience and we have over 25 years of exclusive performance ignition
experience.
MSD goes to great lengths to provide the best performing and most reliable ignition components available. Every
ignition that leaves our building has undergone a battery of tests including a four hour burn-in. The complete MSD
line features a one year warranty and we have an excellent core of engineers, technicians and support personel at
the races and available to answer your calls about ignition systems.
In short, MSD builds the best performing and most reliable ignition products available and we have the wins and
records to back this up. When you’re reading through the magazines or walking through the pits at a race, look inside
the winners’ cars to see what ignition they’re running; MSD Ignition.
Bonus Pointers:
• You don’t need a ballast resistor if you are using an MSD Ignition Control. If you are using a points system
with a Blaster Coil a ballast resistor is required.
• You can run an MSD Ignition Control to a 16 volt battery source.
• Do not run solid core spark plug wires with an MSD Ignition.
• Yes, an MSD will install to a late model LT-1 Chevrolet engine.
Checking for spark with the magnetic pickup as a trigger.
Checking for spark with the white wire as a trigger.
®
TOP TEN IGNITION QUESTIONS TOP TEN IGNITION QUESTIONS
Tech Bulletin
Tech Bulletin
M S D I G N I T I O N • w w w . m s d i g n i t i o n. c o m • ( 9 1 5 ) 8 5 7 - 5 2 0 0 • FA X ( 9 1 5 ) 8 5 7 - 3 3 4 4
© 2008 Autotronic Controls Corporation
FRM29233 Revised 03/08 Printed in U.S.A.
frm29233_tb_top_ten.indd 1 3/14/2008 1:16:36 PM