MSD 8573 Flathead Ford Ready to Run Distributor for '49-'53 Installation - Manual (Page 8)

TACHOMETER INFORMATION
The MSD Ready-to-Run has a Gray wire that provides a 12 volt square wave, 20° duty cycle tachometer
signal that will trigger most tachometers. It is recommended to connect this lead to your tach’s trigger
input wire and check its operation. Note that the rpm limiter is extremely accurate and due to the variety
of tachometers available, there may be differences in the displayed rpm.
PROGRAMMING THE REV LIMIT
A tachometer is required to set the rev limit. The limit is programmed by
running the engine at half the desired rpm, then momentarily grounding
the Gray tach output wire from the MSD. A Gray jumper wire is supplied
to connect to the tach with another tee-splice coming off to use for
programming. A switch may also be installed to ease adjustments of
the limiter (Figure 16). The default rpm limit is 10,000 rpm and the limit
is adjustable from 2,000 - over 10,000 rpm..
1. Start the engine and bring the rpm to half the desired rev limit (for a
6,000 rpm limit, raise and hold the rpm to 3,000).
2. While holding the rpm steady, short the Gray tach wire to ground
for approximately one second. Note that the tach will go to zero
while grounded.
3. The tach will now display the programmed rev limit amount for two
seconds. If this value does not register on the tach, repeat the procedure and try a different ground
source.
4. To confirm the rev limit value, turn the ignition key to the On position (without cranking the engine). The
rev limit value will be displayed for two seconds on the tachometer.
Note: This rpm confirmation only displays when the Gray wire is being used to trigger the tachometer.
Figure 16 Setting the Rev Limiter.
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.
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 (915) 855-7123. MSD technicians are available from 7:00 a.m. to
5:00 p.m. Monday - Friday (mountain time).
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 Autotronic Controls Corporation
FRM30254 Revised 01/12 Printed in U.S.A.