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by Jon Mikelonis

There exists a special kind of satisfaction in upgrading any system on your project car using stock Ford parts. Whether you acquire parts from the wrecking yard or from your favorite parts store, once your upgrade is
complete, you are left with a "warm and fuzzy" feeling that you just got
away with something special. The greatest sense of satisfaction comes from knowing that you avoided yet another donation to your favorite charity, the performance aftermarket.

There are few opportunities for this anymore, so when they come along, we take them. Next to disc brake upgrades, the Ford DURASPARK upgrade over conventional points systems is extremely popular among Ford enthusiasts. Hobbyist sites all over the web show you the steps involved along with the parts required. Many of you have made the switch. Here are just a few quick examples:

DURASPARK Ignition Upgrade by Bob Marr

DURASPARK Ignition II Upgrade by Chris Call

Ford DURASPARK 2 Ignition System by Jason Fletcher

So, rather than reinventing what already exists elsewhere on the web, in this article we are going to show you a few options for upgrading your
existing DURASPARK Ignition with aftermarket parts in the usual,
easy-to-follow FordMuscle method. The options covered in this article will
apply to all of those currently running a DURASPARK Ignition whether you
made a conversion or whether your vehicle was originally equipped with the system. This will also be the first tech article performed on FordMuscle's newly acquired Project RedNeck, our 1978 F250 4x4.

Quick DURASPARK Overview
DURASPARK was introduced in 1973 as an electronic alternative to
conventional points systems. Not until 1976 when the DURASPARK II was
introduced, did the recognizable wide cap design come into use. When most people think of DURASPARK, they visualize the DURASPARK II. Since
DURASPARK II is so commonplace at the wrecking yard, this is the system
that most anyone who has made the conversion has implemented.

Both DURASPARK I and DURASPARK II use a magnetic pickup that incorporates the "Hall-Effect" principle to trigger a spark, an external control box, and a coil. In addition to the wider cap, DURASPARK II uses an improved external control box over the control box offered with DURASPARK I. Even though both I and II use a control box, it's important to note that DURASPARK is classified as an Inductive Discharge Ignition (IDI), not a Capacitive Discharge Ignition (CDI). For the rest of this article we'll refer to DURASPARK II simply as DURASPARK. Before we show you some simple options for improving your DURASPARK, let's talk a little about IDI and CDI.

First off, this section references information found in Todd Ryden's Cartech Book, How to Build High-Performance Ignition Systems. For a complete overview of performance ignition system alternatives, Todd's book is a great buy. To simply generate a stronger spark from your DURASPARK without too much research and decision-making, follow along here. Now on to IDI vs. CDI.

While there are a number of aftermarket IDI ignitions and upgrades, when you think of IDI, think of an OEM ignition system. Both conventional
points systems and the DURASPARK ignition fall into this category. IDI
ignitions depend on the coil to receive a 12-14 volt supply from the
battery, convert that voltage to over 10,000 volts, and then release that
voltage each time it is triggered by the distributor. Increase your RPM
and this all has to happen quickly, very quickly. Herein lies the
compromise of an IDI ignition. While IDI ignitions provide a long and
strong low RPM spark, there is a potential for weak spark at high RPM
because the coil does not have enough time to saturate between firing each cylinder. At what exact RPM an OEM IDI ignition without an "add-on" begins to breakdown, depends on the exact system. To keep it simple, figure that an OEM IDI ignition will perform just fine under 5000 RPM.

Most performance ignitions fall into the Capacitive Discharge Ignition
(CDI) category. Think CDI and think of the common 6-series ignition boxes from MSD, Mallory, and Crane. CDI ignition boxes draw voltage continually from the battery and store up to 500 volts. The 500 volts is always ready to be sent to the coil where it is then converted to the ultra-high voltage required to cross the spark plug gap. With a CDI box, you can depend on consistently complete sparks throughout the entire RPM range. By nature, a CDI produces a shorter duration spark at low RPM than an IDI. This is why the units have been designed to fire multiple sparks within the same cycle. To quote directly from Todd Ryden's book... "CDI ignitions offer improved idle, quick starts, crisp throttle response and improved high-RPM performance."

DURASPARK Upgrade Alternatives
Having an ignition system that is dependable throughout the entire RPM
range is reason enough to upgrade your OEM Duraspark. However, by
introducing an inductive "add-on" or by converting to a Capacitive
Discharge Ignition you will see the most practical improvement during
startup and idle. There are a number aftermarket components from MSD,
Crane, Mallory, and Performance Distributors that will allow you to
improve your DURASPARK. We tried out both an IDI "add-on" from Performance Distributors and an easy-to-install CDI unit from Mallory.

Mallory HyFire 6EZL (CDI)
The first thing any enthusiast would notice about the Mallory HyFire 6EZL is the distributor-type terminal end protruding from the case. No, that's not an integrated coil. That terminal-end is how Mallory Ignition made the
HyFire 6EZ and 6EZL (L for rev limiter) the quickest CDI box install on the market. Because the Hyfire 6EZ and 6EZL uses your factory coil to
trigger the system, the unit can be installed without tapping-in to your
wiring harness. Simply run one of the two included coil wires from your
factory coil over to the HyFire ignition box and the system can now "talk"
to your factory ignition. When coupling the Mallory HyFire 6EZL with a DURASPARK system, like we've done below on Project RedNeck, not tapping into your vehicle's wiring harness is very convenient. That's right, the complete DURASPARK system remains intact, including the DURASPARK ignition module. The EZ's digital microprocessor operates off 8-16 volts and provides 135 mJ of spark energy.

While MSD is the name most think of when it comes to "red box" CDI
ignitions, this Mallory unit stacks up very well against the MSD 6AL.
Here's a feature by feature comparison, and remember the Mallory unit
includes a coil. Popular mail order companies offer it for around $220.
Last we checked, that's less than the MSD 6AL.

Mallory HyFire 6EZL
Digital or Analog
Multiple Spark
Rev Limiting
Primary Output Voltage
Secondary Output Voltage
135 mJ
Spark Energy
115 mJ
.6 amps
Current Draw
Per 1000 RPM
1.0 amps
Operating Voltage Required
Coil Included
Extruded Aluminum
Housing Construction
Cast Aluminum
Popular Mail Order
Retail Price
(as of 1.2.2007)

Continuing from our first pass of upgrades on Project Redneck, the
factory DURASPARK was operational yet a bit rough at idle. A clear
opportunity to upgrade and convert an IDI to CDI.
Here's the HyFire 6 EZL, included coil, and two coil wires. The HyFire
uses an attractive extruded aluminum case.

I found a cool space to install the box above the passenger-side fender
well of the F250.
The red ring terminal and wire is meant to be connected directly to a
12V battery source.

The existing coil to distributor wire is removed.

The HyFire is triggered by the factory ignition (points or electronic).
Here, the HyFfire is connected to the factory coil with an included coil

The included coil wires with the HyFire EZ and EZL are long to
accommodate your particular mounting requirements. Using some leftovers from the new spark plug wires on Project RedNeck, I made up a custom wire using my new wire
Right size wiring makes for a cleaner install. Tip: Don't let the
teenage 5.0 liter guy down the street know you've got plug wire crimps.

As with the CDI box, mount the coil in a open area away from direct
heat. This included coil will now be responsible for the heavy lifting
while the factory coil is demoted to its new position of signaling the
The HyFire box has an integrated connector for the Mallory coil.

I connected the second included coil wire to the Mallory coil.
Next, I routed the coil wire along the firewall, across the intake, and on to the DURASPARK cap.

I made the final connection from the CDI box to the negative side of the battery.
Startup indicated a noticeable improvement in idle quality and
smoother throttle response.

(Performance Distributors DURASPARK)


In This Article:
Already equipped with a factory DURASPARK ignition? Whether your Ford came with one originally or if you've replaced your mechanical distributor with a DURASPARK system, FordMuscle shows you a few upgrades via Project RedNeck.

Purchased in November 2006, FordMuscle's 1978 F250 Custom 4x4 came equipped with a DURASPARK ignition. While operational, we knew it could be improved.

The advantages of a multiple spark ignition (capacitive discharge) can be found in "6-series" CDI boxes like this one from Mallory. We added the Mallory HyFire 6 EZL in a snap at watched for improvement.

While the Mallory Hyfire improved idle and throttle response, we noticed intermittent behavior. The culprit was our stock DURASPARK distributor which we then replaced with a custom calibrated unit from Performance Distributors.


An IDI (inductive discharge ignition) upgrade can be performed using this Dyna-Module and Inferno Coil kit from Performance Distributors. It is meant to work in place of the DURASPARK Ignition module.



ACCEL 300+ Perma-Crimp
Spark Plug Crimps
Cut-to-fit plug wires like the Mallory 8mm ProSidewinders used on page 2 of this article require you to do the stripping and crimping. This results a tighter looking set of plug wires that are much easier to manage. To do the job right you'll need a set of professional-grade wire crimps like the ACCEL 300+ Perma-Crimp Tool. Take a look at caption 13 on page 2 of this article to see how clean the crimps come out using this tool.

Constructed with a heavy duty hardened steel frame and molded non-slip hand grips. The adjustable ratchet mechanism produces consistent factory style crimps. The ACCEL 300+ Perma-Crimp Tool is the only crimping tool supplied with three removable stripping/crimping die type jaws: one for 7-9mm spark plug wires, one for primary wire terminals, and one for pre-insulated terminals. Where to buy?



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