Duraspark II Ignition System

Bang for the buck, the Duraspark II is hard to beat as a triggering device for an electronic ignition system. Coupled with either the stock ignition box or an aftermarket control box, it is a tough, readily available, reliable distributor.

Ford began using electronic ignitions in 1973 and introduced the Duraspark II system in 1976.  The biggest change, apart from the control box redesign, was the large distributor cap to handle the increased spark energy.  The system consists of a magnetic reluctor and pickup in the distributor, and an ignition module to trigger the coil. Typically, the distributors have both mechanical and vacuum advance mechanisms. The curve is reset by using inexpensive springs and adjustable advance units. They can be found on both 200 and 250 engines and are interchangeable.

They are a direct fit on older 200/250 engines as well. Pictured above is a Duraspark from an '81 Fairmont 200 ci engine, installed on a '73 Maverick 250 ci engine.  If you wnat to get one from the auto parts store, make it easy on the clerk and just ask for a distributor from a '79 Fairmont.

The Stock Ignition Module

The stock ignition wiring diagram looks daunting but all of the wiring is contained within the harness. This leaves only two connections which have to be made: a red wire which is connected to a switched 12V source and a white wire which goes to the start terminal of the ignition switch. The white wire is optional. When used it retards the spark a couple of degrees to reduce the load on the starter (an enterprising hot rodder might hook this up to a nitrous switch to retard the spark when the juice is on).

When selecting the module, the one to ask for is the one with a "blue strain relief" or the "49 state" module.





Using an Aftermarket Control Box

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.

Wiring with stock module

Wiring the MSD as a stand alone

The GM Module

The Duraspark can also be very simply wired to a GM 4-pin module for a very clean and easy setup.  The module has to be mounted on an aluminum or steel plate so that heat can be dissapated.  This is an incredibly easy way to add a Duraspark.

Tuning

Spark plug gaps may be set much wider with the Duraspark. Using the stock module, set plug gaps between .045" - .060". With an aftermarket module, check the manufacturers recommendation. On my coupe, I am using the MSD6A as a stand-alone with plug gaps of .054".