Pictures and information by Karl Schluter. Copyright.
Stage 4
The aftermarket (MSD, Mallory, Jacob and Crane etc) supply
spark boxes that are either Inductive or CDI systems, MSD do one that’s both.
Going to more expensive boxes will get you a built in rev limiter (handy for
racing or as a safety device etc) plus other useful features. Start retards are
available for high compression as well. Not all are multi spark boxes.
Pertronix have one that you can adjust the firing of the second spark for best
results.
The companies from the US are all very close with digital being the way things are going over the older analogue type systems. These boxes can run with the stock points just like the kitset systems with the same benefits but are more expensive, you get what you pay for. Most of these boxes can be run with the converted Lucas distributor or donor distributors mentioned in our previous articles. Check with the company’s web site and tell them the donor models distributor or donor parts.
Beware of buying a second hand module/spark
box as they can be damaged like all electronic devices. Most of these
aftermarket CDI boxes prefer the use of a basic timing light instead of a “Dial
back” timing light when setting timing. The multi firing can confuse some
timing lights.
Note: The aftermarket Spark boxes by Crane, Mallory and MSD
etc mentioned above will run off Points, the Magnetic pick up and reluctor
system (US, European, Australian or some Japanese), or the optical system used
in aftermarket kits. Not all modules will run off Hall effect distributors,
which are sometimes used, by car companies and the aftermarket.
Handy tips for a long
living ignition Module,
A few tips for factory
Modules and aftermarket Amplifiers/boxes:
·
1, Rubber mount the box if its not meant to be on a heat
sink like a factory module (eg GM HEI module).
·
2, Mount the box so air can move over it to cool it. NOT in
a closed glove box!
·
3, Mount the box/module so water cannot collect inside it.
Do not silicone seal the box to anything.
·
4, For CDI and other high power systems, a capacitor wired
in parallel off the two main battery wires to the box will add years to it, (Specs
-16VDC 20v max surge, 10 amp. 26kufd, 5000mf or bigger) .
· 5, Don’t use a Battery master cut off switch on the earth side- as on switching off, the spark box can try to arc to earth inside!
·
6. For MSD, Mallory and Crane multi spark boxes, most
companies prefer you wire the main power and earth to the battery direct-not
the starter solenoid or alternator or a chassis point, this helps prevent
spikes and surges, as will running a starter and alternator in top condition.
Check wiring to the battery as per their instructions.
·
7,Voltage between the keyed + wire and the positive battery
wire on the above systems should be within 2 volts of each other for a long
lasting module-if its not, check out why.
·
8,Use a fuse in the main module battery feed, 1 amp per 1000rpm,
a 6-8 amp fuse is about right. Run the wires leading to a Magnetic pick up
distributor alway from the Spark Boxes power wires. If all the wires go through
a grommet in the firewall, use another hole and grommet for the Magnetic pick
up wires. If you use the correct ratchet crimp tool, then crimp
fittings are fine. If you want, solder as well but avoid overheating the wire
strands, as they will fail as will poor soldering.
·
9, Make sure the factory type spark boxes earth
wire is earthed to the chassis or a paint/rust free area. Use a “star”
washer with teeth for best contact. Wire the earth only like this if the
manufacturer did the same; otherwise run the earth direct to the battery.
·
10, The two distributor pick up wires (if using a magnetic
distributor) may need reversed if the engine timing is way off or fails to
fire. Twist these two wires together along their lenght (to stop EMI inference)
and install them away from ignition coil or spark plug wires.
·
11, Point type voltage regulators for older generator
charging systems can spike some factory type modules.
·
12, Don’t weld on the car without removing these modules
(yes-remove!) OR unplug the module, distributor and battery at least. If
welding on the car, keep the clip on welding cable close to the work area. The
best idea is to remove the Spark box.
·
13,Booster/jumper cables can also blow aftermarket boxes as
will “Booster starters”, just the same as on some factory cars!
·
14, Do try to run the same companies recommended coil for
that module/box for best results. Often different coils work best in different
rpm ranges, the Spark boxes manufacturer can advise on what coil for your end
use.
·
15, If you have a choice, use a cap with brass terminals, they
don’t corrode as fast with ionised air. Drilling a cap with 1/8 holes at rotor
level or picking a cap with a vent and wide spaced terminals will
also help.
·
16,Not all of these CDI boxes run with aftermarket or
factory rev counters, contact the companies or me via this address; avocalea@xtra.co.nz.co
·
17, Some aftermarket boxes will not run correctly with
factory fuel injection systems like on Rover V8’s, an adaptor from the ignition
boxes companies will correct this in most cases.
·
18,Some hot spark systems run best with an earth wire or a
small cable, running from the engines cylinder head to an earth point. V8’s
should have a cable from head to head then to the chassis, this can improve
spark plug performance.
·
19, Relays in your cars wiring can result in 300v to 500v
voltage spikes that will damage sensitive electronics like aftermarket
ignition boxes. Use a Relay that has an internal diode fitted to protect
against this, Hella make several of these.
·
20, Use good quality spiral type coil and spark plug leads.
Do NOT use solid core cables, as these will upset the ignition
module as well as items like rev limiters etc.
NOTE: I have not offered
detailed wiring instructions as these can be found by using:
·
1,The donor cars wiring diagram, (visit a library),
·
2,The aftermarket ignition manufacturers instructions,
·
3,A good auto sparky,
·
4,Google!
·
5,Contact me via avocalea@xtra.co.nz
for non-Japanese wiring as I have some wiring diagrams/tech as well.
Remember it’s not rocket science! Books for good ignition “How to” tech, (these
are the BEST of a few I have brought, I also recommend Amazon.com).
1.
Custom Auto
Electrickery SBN 0
949398357,
Frank
“Choco” Munday .
2. How to build High Performance ignition systems, ISBN
1-884089-72-0
Todd
Ryden .
3. Performance ignition systems ISBN
1-55788-306-8
Christopher
Jacobs PH.D, E.E
4. MSD Ignition Wiring diagrams and tech notes
Your
nearest good auto parts shop.
5.
Performance electronics for
cars, Jaycar BS-5080
·
Silicone chips Electronic Projects For Cars Vol. II
Available
at:https://secure4.vivid-design.com.au/jaycar2005/sitemap.asp
SITES:
·
Good website for
explaining different systems :
http://www.jetav8r.com/Vision/Ignition/CDI.html
http://www.centuryperformance.com/default.asp
·
Good site discussing
lead types:
http://www.magnecor.com/magnecor1/frequent.htm
·
Websites/ suppliers
for kits etc Adapted Distributors:
Barry in NZ at http://www.qualityrebuilds.com/
Kit sets Modules:
https://secure4.vivid-design.com.au/jaycar2005/sitemap.asp
Suppliers of the Lumenition kits:
http://www.denaploy.co.uk/autocar/index.html
Clapham Industries in NZ, PH (03)366 7472 fax (03) 366 7471
Ignition Companies:
http://www.classicheads.com/Electronic_Ignition.html
http://www.msdignition.com/1sitemap.htm
(Mr Gasket owns Mallory, Accel, and Jacobs)
http://www.malloryperformance.com/
http://www.cranecams.com/?show=browseParts&lvl=2&prt=3
http://www.autopia.co.nz/rite_tec_js.htm
https://secure4.vivid-design.com.au/jaycar2005/sitemap.asp
Barry in NZ offers
conversions as well http://www.qualityrebuilds.com/
Disclaimer:
The advice and guidelines given in these articles are given in good faith.
The owners and managers of the Galeforce Zephyr site will take no
responsibility for any injuries or loss sustained while carrying out the
described tasks and procedures or any consequences arising. Please read
the Safety First
Article