Ford Duraspark 2 Ignition System

The Ford Duraspark II electronic ignition system is a great upgrade and economical solution over a points type system. It is pretty much maintenance free. The
Duraspark II system was used on all small blocks starting in 1977. The system is solid for most mild steet rod applications.

There are four basic components to this ignition system – the distributor, ignition
module, the coil, and the wiring harness.

The Distributor – The key here is to get a distributor that is compatible with your cam type, has vacuum advance, and has a decent mechanical advance curve. If you are using a roller cam and you need a steel gear – use an '85 Mustang 5.0L GT distributor for a 5-speed. This distributor has vacuum advance and a great advance curve straight from the factory. If you are using a flat tappet cam your first choice should be an 82-84 5.0L Mustang HO distributor. This distributor also has vacuum advance and a good curve. Any 77-84 302 distributor will work with as long as the car was carbureted (NO CFI – throttle body injection), just don't forget to use a drive gear that is compatible with your cam.

Advance Curve Reprogramming – To get the most out of these distributors an advance curve should look like this: centrifugal advance – 0 @ 1,300 rpm, 11 @ 2,000 rpm, 20 @ 5,000 rpm; vacuum advance – 0 @ 4.5″ Hg, 11.5 @ 8″ Hg, 20 @ 12.5″ Hg. Okay, so what's the big deal about vacuum advance? How about your gas mileage – with a vacuum advance distributor your gas mileage will be significantly higher than with a mechanical
advance distributor alone. If it is a strip only car then it won't matter – vacuum or mechanical.

Ignition Module – This is really pretty simple – get the one with the blue color plastic where the wires go into the module. There are a variety of grommet colors but the blue one is the easiest to get. When mounting the unit be sure it is grounded good and away from high temperatures. Heat is what kills electronics so a little prevention up front will go a long way to long term life. The part numbers for this unit are as follows:

  • GP Sorensen: EL107M
  • Standard: LX203
  • ECHLIN-Napa: ECHTP40
  • Niehoff: FF402

The Coil – Just about any coil will work but stick to the good stuff – Stock, Accel, MSD, Mallory, or Jacobs. The stock Ford TFI coil is an excellent performer for the price. More on this in Part 2. Whatever you choose, mount it away from heat and vibration for the longest life.

Wiring Harness – It is always easiest to use the factory harness with the factory connections, but be careful, if you are fabricating your own harness do a good job of soldering or you will end up with electrical issues down the road.DS2wiring

Wiring diagram graphic – As you can see, wiring the Duraspark Ignition is pretty much straight forward. It is, for the most part, a "stand alone" system needing only one outside power connection. The control box gets its only power through the red wire in the 2 pin connector. This needs to be a 'hot in start and run' source. And a solid 12 volts. The white wire in the 2 pin connector may optionally be connected to the S terminal of the starter solenoid, this provides a cranking indicator to the control box, retarding the timing a few degrees for ease in starting. The rest of the wiring uses the factory harness. The color of the wires in the harness may differ for different years, but the colors on the control box and the distributor are the same. The green wire goes from the control box wires to the negative(-) terminal of the coil. This is where a TACH may be connected. The orange and purple wires run from the control box to the pickup inside the distributor. The black wire runs to the distributor housing and is the control box's only ground. It is a good idea to splice into this wire and run an additional solid chassis ground.

Odds and Ends

Use the cap and rotor combo appropriate for the year/application distributor you are using. And it is never a bad idea to get a premium cap with brass contacts. Under some circumstances, where you have space issues around the cap, you may need to retain the old style smaller cap but you can also step up to the larger diameter (EEC) version caps and rotors for better crossfire protection if you have the room. The cap posts are female instead of male, but once again follow the year application for the right cap /rotor and the matching spark plug wires. And speaking of plug wires stick to the name brand stuff for best results. Part numbers are in Part 2!

The Duraspark distributor is easily wired to an MSD or other aftermarket ignition system.
The MSD can be used as a stand-alone or in conjunction with the stock module.

Continue on with More DuraSpark Notes >>>

More Duraspark Notes 3

This page is parts notes and part numbers that have been accumulated from a variety of sources that make the Control Box selection a bit simpler. Some you may already know but you may find some new info here.

A new install kit part number 30812 is available from Painless Wiring. It has pre-terminated ends with Weatherpak connectors. Makes for a quick easy conversion.

The Ignition Module The modules are identified by the color of plastic grommet that connects the wiring to the module housing. The most common is the blue grommet.
All Dura Spark modules are full 12-volt units. Anything less than 12 volts and the module
becomes unstable. The black wire that comes out of module and goes to the four-wire connector is the ONLY GROUND FOR THE MODULE. It normally grounds through the distributor wiring to the distibutor housing. You may want to splice into it and take the new end to a good, solid chassis ground. The DuraSpark module can be reliably triggered by any of the factory, and most aftermarket, magnetic pickup coils, so it can by used no matter what kind of electronic ignition you have. (Including a GM 4 pin module but thats another tech article! BzeroB

 Note The Duraspark box has a neat feature built in to it. It has an extra on-start retard wire that you can hook either to a switch, an rpm activation switch or to a boost retard switch, great for boosted carb setups or heavy compression setups

  • Blue box – retards 4 degrees (most common)
  • White box – retards 14 degrees (very early 80's carb 2.3t)
  • Yellow box – no retard (California box)
  • Orange box – retards 6 degrees (industrial box)
'74-'91 DuraSpark Ignition Control Modules
OEM Ford P/N Ford Service P/N Motorcraft P/N
D4AE-12A199-A1A

Black grommet

D4AZ-12A199-A DY-157
D4AE-12A199-A2C

Black grommet

D4AZ-12A199-B DY-157A
D4AE-12A199-A1D / A2D

Black grommet

D4AZ-12A199-C DY-157B
D5AE-12A199-A1A / A2A

Green grommet

D5AZ-12A199-A DY-166
D5AE-12A199-A1B / A2B

Green grommet

D5AZ-12A199-B DY-166A
D5AE-12A199-A1D / A2C / A2D

Green grommet

D5AZ-12A199-C DY-166B
D6AE-12A199-A1A / A2A

Blue grommet

D6AZ-12A199-A DY-184
D6AE-12A199-A1B / A2B

Blue grommet

D6AZ-12A199-B DY-184A
D8VE-12A199-A1B /A2B

Blue grommet

D7AZ-12A199-B DY-184B
D8VE-12A199-A1C / A2C

Blue grommet

D9VZ-12A199-A DY-184C
Blue grommet F2PZ-12A199-AA DY-683

Update for all DY-184 modules.

D8AE-12A244-AA

Yellow grommet (3-wire 3rd plug)

D8AZ-12A199-A DY-237
D8AE-12A244-AB

Yellow grommet (3-wire 3rd plug)

D9AZ-12A199-C DY-237A
D8VE-12A199-A1B

D8VE-12A199-A2B

Red grommet

D7AZ-12A199-A DY-204
D9DE-12A199-B1A / B2A

Brown grommet

D9AZ-12A199-B DY-249A
D9EE-12A244-A1A /A2A

White grommet

D9FZ-12A199-A DY-250
E1AE-12A244-A / AA

E1AF-12A244-AA

E2FF-12A244-AA

Yellow grommet (2-wire 3rd plug)

E1AZ-12A199-A DY-297

Wiring Up a Ford G Series Alternator

Now that we figured out which one to use and went out and got one how can we wire it up?

Upgrade to a Ford 1G Alternator (100 Amp) and keep the external regulator

This alternator is a quick and dirty install/upgrade from a 55/65 amp. (Lester #7742) Sources for this one are 88-90 Ford Taurus; Lincoln Continental; Mercury Sable with 3.0 and 3.8 motors. This is an externally regulated unit so it is a good upgrade to keep your wiring intact.

Wiring up a Ford 2G Alternator eliminating the external regulator

This is the next level up and a very similar upgrade. Simple and effective solution with a one-wire hook-up.

Upgrade to a Ford 3G Alternator eliminating the external regulator and harness

The 3G alternator comes in outputs all the way to the 130 amp version. This is the one to get. Now it does come in a couple of flavors. Here are the details. The three choices are a 7 inch pivot mount, an 8.25 inch pivot mount and a side mount with horizontal bolts. The ones I will concentrate on here are the two pivot mount types because they closely resemble the factory style mount.

  • 65 Amp – Lester 7716
  • 75 Amp – Lester 7735
  • 130 Amp – Lester 7771

The D shaped regulator connector has 3 terminal lugs labeled I, A and S. The hookup is really simple.

  • I is the ignition on wire. This is a keyed hot wire.
  • A is the voltage sense wire. You loop this directly to the red B+ terminal on the back of the alternator.
  • S is the stator wire hooked to the stator connection which is the small spade connection right next to the large D-shaped connector.

The new charge wire goes from the red B+ lug to the battery. A 6 gauge or larger wire and a mega fuse in the 175/200 amp range complete the hookup. These can be salvaged from 90's Ford Contour / Mystiques. The diagram shows the wire hookups and the most common Ford wire colors.

*** The wiring graphics are courtesy of RJM Injection Tech