Electrinic Ignition options

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Cribbs74

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I finally was able to start the Mustang today for the first time in 23 yrs. The elation was short lived as I lost spark after about 20 seconds of running. I traced the problem to the mallory Unilite module.

What I am wanting to know is if there is a better module available such as pertronics or maybe even a factory electronic distributor I can use.

Ron
 
One of the most popular retrofit triggered ignitions is the Pertronix, although there are others. Surf the internet, ( I know you have a computer or you wouldn't be on here ). Some prefer the MSD Ignitions, it's all personal preference really. I've never run a Unilite , I've heard them called "Neverlights", but it seems that the Hall Effect magnetic triggers work better than the light beam optical triggers.
 
Crribs74,
Looks like the Unilite module is still available for about $ 80 on Summit.
Before making that purchase, I would download the instructions on Summit and check the ignition coil requirements and ignition feed voltage requirements and possibly keep a new module alive for a long time.
Boilermaster
 
I've had the original Pertronix for over 30 years and it was still going strong when I pulled the engine for a rebuild.
 
I’ve checked primary and secondary coil resistance.Verified my inline resistor is the correct ohms value cleaned all connections Triple checked my wiring against the Mallory instructions on the website. It started, ran then quit. It will still fire intermittently spark at the plug comes and goes.

I wasn’t needing help with troubleshooting. I was just wondering what you guys use and possibly an associated part number. I have been looking online at the pertronix units.
 
My distributor is a Motorcraft. Looks to be a later replacement as it has only one port on the vacuum diaphragm.

As an aside I went ahead and installed points in it. It fired right up.
 
Some info from over at the the Pantera group:

The Ford Duraspark ignition is reliable, it performs well, and parts remain readily available. The Duraspark I ignition was Ford's first high output ignition, featuring dynamic dwell which charges the coil perfectly over a wide range of engine speed. Thus it is the preferred ignition (the original application was California only - 1977/1979), but the only aftermarket wiring harness available is for Duraspark II. The Duraspark I coil and the Duraspark II wiring harness require modifications to use these parts for a Duraspark I application, therefore this choice is only recommended for folks willing to perform the modifications (which aren't that difficult). The Duraspark II ignition is a simpler plug & play installation.

Duraspark I (red wire grommet) SMP LX210 ignition module and SMP FD477 coil; 0.060 plug gaps.
Duraspark II (blue wire grommet) SMP LX203 ignition module and SMP FD476 coil; 0.050 plug gaps.
Duraspark ignition wires SMP 69404

A Duraspark II wiring harness is available from Painless Wiring (p.n.30812), or American Auto Wire (p.n.500918); be sure to use the appropriate coil with the ignition module you have selected. The Duraspark I ignition does not utilize a ballast resistance.

1676170253955.png
Set the ignition timing to the following spec: 16° to 18° initial advance; 20° centrifugal advance fully in between 2800 to 3200 rpm; this equates to between 36° and 38° total advance. Street engines (operated at partial throttle) should have 10° vacuum advance connected to ported vacuum. In spite of what you may have read elsewhere, a combustion chamber of fixed design (factory Cleveland), utilized with a piston dome of fixed design (flat top), with an identical dynamic compression ratio (8.0 or less), and with a fuel of fixed octane (91 US/Canada), shall require the same ignition calibration.

If a Ford Duraspark distributor is utilized a distributor “sleeve and plate assembly” marked 10L or 10R and replacement centrifugal advance springs shall be required to properly calibrate the centrifugal advance curve. A sleeve and plate assembly with a wider “notch” can be modified to reduce the width of the notch; the proper notch width for achieving 20° centrifugal advance is 0.410”. Ignition Engineering of Anaheim California can rebuild and re-curve a Duraspark distributor for you (telephone 714-334-9143). The MSD 8477 distributor is a good substitute for the factory distributor, and the MSD magnetic pick-up is Duraspark I or Duraspark II compatible.

10L%20advance_zpsfm4hpuqx.jpg
 
And a little more info on the Duraspark 1:

GNITION SYSTEM IMPROVEMENT

If the 351C in your car is equipped with a breaker point ignition, or even an old and tired breakerless ignition then it must be improved. A smooth and precise operating "high output" breakerless ignition system is just as essential to a high performance engine as raising the compression ratio. There are many ignition systems to choose from. One possible ignition system choice that employs Ford parts is a Ford Duraspark distributor calibrated for 20° of centrifugal advance in by 3000 rpm, triggering a Duraspark I module and a Duraspark I coil.

California was the only state in which Ford vehicles were equipped with Duraspark I ignitions; Ford enthusiasts outside of California were not aware of the existence of this ignition and had no experience with its performance, which was a shame. The Duraspark I ignition was also known within Ford as the "high output ignition", it was much more than a different Duraspark module, it was considered an entirely different ignition system than the Duraspark II ignition system. It was Ford's first high output ignition system, and Ford's first ignition system to employ "dynamic dwell". The Duraspark I ignition was utilized in all California V8 equipped applications in 1977, and limited to California 302 V8 applications in 1978 and 1979. The Duraspark I ignition module is identified by its RED wiring sealing block.

At the heart of the Duraspark I ignition was a special ignition coil having a very low primary winding resistance. The coil was also operated with no ballast resistance; therefore current flow in the primary windings was substantially increased in comparison to the primary current of Ford's standard (Duraspark II) ignition system coil. The core of the Duraspark I coil was designed to accept a much higher magnetic charge from the increased current flowing in the primary windings, thus producing a substantially higher voltage to the spark plugs. The higher magnetic charge also allowed the coil to reach "full charge" more rapidly than Ford's Duraspark II ignition system coil. Spark intensity was greatly increased ... especially at higher rpm. If this coil's primary winding had been charged with the conventional "fixed-dwell" control utilized by the Duraspark II electronic ignition system it would have overcharged at low rpm and overheated. Therefore an ignition module with a unique primary current control circuit was required to compliment this coil.

Differing from the various Duraspark II ignition modules, the Duraspark I module didn't control charging of the coil in the conventional way. The Duraspark I module utilized dynamic dwell, meaning the module constantly adjusted dwell based on current flow in the coil's primary circuit, independent of engine speed. This prevented over charging or under charging the coil throughout the motor’s rpm range. Dwell therefore varied with respect to the degrees of crankshaft rotation but remained relatively constant with respect to actual coil charging time; and the coil was properly charged throughout the engine's operating range.

The Duraspark I ignition produced the most consistent and most potent spark of any Ford ignition. This was Ford’s best ignition for igniting lean mixtures or rich mixtures, which was the purpose for its existence. The ignition ignited mixtures the Duraspark II ignitions could not. The dynamic dwell feature gave this module good high rpm performance too as the coil was charged properly (never under-charged or over-charged) from idle to 7000 rpm. This ignition’s design was more elaborate than the design of the Duraspark II ignition, and therefore it was more costly for Ford to manufacture (replacement Duraspark I modules cost several times the price of replacement Duraspark II modules).

DUASPARKINFOPAGE_zps04acdfcd.jpg~original


DistributorGear_zps5177cdd4.jpg~original
 
i used pertronix also. i just replaced the points with the unit... nothing else. even used the resistor wire so as not to play games with the tech. yes pertronix says use 12v not the resistor wire. but i ran for 6 yrs and no issues and tach worked fine.
 
I finally was able to start the Mustang today for the first time in 23 yrs. The elation was short lived as I lost spark after about 20 seconds of running. I traced the problem to the mallory Unilite module.

What I am wanting to know is if there is a better module available such as pertronics or maybe even a factory electronic distributor I can

I finally was able to start the Mustang today for the first time in 23 yrs. The elation was short lived as I lost spark after about 20 seconds of running. I traced the problem to the mallory Unilite module.

What I am wanting to know is if there is a better module available such as pertronics or maybe even a factory electronic distributor I can use.

Ron
Cribbs, the Mallory Unilite is an excellent system. Been in nonstop production for decades and is currently produced as a replacement module (as boilmaster previously mentioned) and full distributor by Mallory/MSD. After sitting for 23 years hard to say what happened to yours. For what it's worth, I run a Mallory Unilite in my 428 SCJ, 427 Cleveland and 351 Cleveland with excellent results. Good luck with your project.
 
Cribbs,
I have ran the Unilite distributors for many years. There was a time that all replacement modules were being made in some foreign land with questionable quality and I believe that quality issue has been resolved. I have had a couple go bad in the 20 plus years and still currently running them. I have seen and heard of many issues with Pertronics and MSD also. Just a thought because I know firsthand that the modules do not like power surges, did you have a battery boost charger or jumper cables when you first fired it up ? Just that would destroy a module very quickly.... I guess it will end up what your most comfortable with... I always keep a spare module in the trunk.
Thanks, Jay
 
I would look at a Duraspark I conversion, MSD, or Daytona Sensors conversion with a re-curved Duraspark distributor. If you are using the car as a cruiser, the Pertronix I would be an easy and cheap fix. I won't use Pertronix anything on a high performance build. Chuck
 
I use a Pertronix Ignitor II, matching coil and a full 12 V power supply. The distributor is a factory Motorcraft set up with a 10L limit slot etc. I'll not go further into that here, but with 14 degrees initial timing, 20 degrees on the crank and an adjustable vacuum canister set at about 4-6 degrees, it pulls like a train up to and past 5k rpm.
If I were to redo the ignition, I'd definitely look seriously at the DuraSpark and curved as mention above.
For a quick fix the Pertronix I would be a good start........... literally.
 
If you go Pertronix, be aware that sometimes the magnet collar can be a problem. Especially if the collar gets dropped and a magnet is broken. It messes up the magnetic field.
Or a magnet might even be missing.
I've had one in my Opel for 20 years. Never a problem, but I carry a spare...just in case.
 
I had been working on the earlier Ford electronic ignition systems from the early-70s, and their early Electronic Ignition and Electronic Engine Control systems (EEC 1 and EEC 2) from the mid-70s. Back in those dark days we has all kinds of problems with Electronic Ignition Modules causing a "Dies While Driving" problem - something the factory said was blown way out of proportion back then (they were in denial). The factory-required test equipment for those systems was not worth the powder to blow them to hell, as they tested only "then current" system circuits, not "while driving" during dynamic conditions. I found what caused those Ignition Modules to intermittently fail were heat, vibration, and shock.

Rather than use the Rotunda test equipment I used a brass shammer and an oscilloscope. I would set the Sun scope secondary ignition pattern to Superimposed Pattern, then while watching the scope begin to tap, later begin to hit harder, the ignition module (in its durable metal encasement),, looking for any shock instigated flicker or pattern deviation, If I saw such a flicker or pattern deviation I replaced the module. Otherwise I would look at other issues (plugged fuel filter, bad fuel pump, etc.). The technique was so effective that the number of actually bad units proportionately in the replaced units under warranty caused Ford to realize our return of modules that were actually good was at a near zero level in comparison to other dealerships. They actually flew an engineer out, unannounced, to see what we were doing.

One of the first things the engineer asked me is if I was turning ignition work away. I laughed and said, "No, I found a really good way to test these modules that is pretty much foolproof." "Oh, really? What makes you think it is foolproof," he asked (in front of our Service Manager, who was getting nervous). "Well, for one I do not get customer comebacks on cars I do not install a replacement module on, I stopped wasting time on replacing modules and hoping for the best, I spend more time tracing down the actual problem they are having - usually plugged fuel filters," I said. Further, if what I was doing was not effective you would not have flown out here from Michigan to see what we are doing different, right?" Yeah, our test technique was so good that they saw the deviation from other dealership repairs. Modules replaced under warranty were often required the dealership to send warranty replaced modules back to the factory for deeper inspection. Modules found to not be bad resulted in the dealer being back-charged for a needless repair. The modules we were sending them were indeed bad, our charge-back rate for replaced modules was zero. A statistical near impossibility based on what they saw elsewhere across the country. There was something definitely different with our dealership... And their numbers showed it.

The engineer, Lee Sanders, sat back and said (almost mockingly), "Okay, will you share with me what it is you are doing so special?" "Sure." Then I described how I use a brass mallet and oscilloscope to test the modules. He looked art me incredulously, and said, "You have got to be kidding me!" So, I invited him to come back to my shop stalls so I could show him. As it turned out I was working on a 1978 Ford Fairmont with a 302 2v engine, which had come in for a routine tuneup. It also had a Red Grommet electronic Ignition Module (more prone to failure than the Blue or Black Grommet modules). I pointed to the shelf under my main work bench and told him to pick any Red Grommet module he saw, all which had been replaced by me. He grabbed one and I told him it is one that failed my mallet test. But, before testing that old unit I told him I would test the 78 Fairmont's current module. I hooked up the scope, started the engine, put the display in Superimposed mode and began to tap the module as he watched the screen. I began hit hit the module harder. "Did you see anything," I asked. "No," he said. "That is because this is a good module, at least for now," I said.

I then killed the engine, and installed the old module, and restarted the engine. I told him to watch the screen carefully and look for any flicker or change in the ignition pattern. I began to tap, then asked, "Did you see it?" "I think so, I'm not sure," he said. So I tapped again, a little harder. That time he saw it. "That, Mr. Sanders, is a bad module." How can you be so sure," he asked. "Here is how..." I hit the module, hard, and the engine died immediately.

Those modules had all their circuitry sealed in epoxy. So I could not dig into the boards. But, I told him I surmised that during assembly not all soldered connections are solid, There may be some cold joint soldered connections, or other components that begin to fail when exposed to the heat and vibrations we subject the modules to under an engine hood.

He asked me to re-re-repeat the same test using several different old Red Grommet modules I had under my bench (I had a lot as I used them as spacer blocks for some trucks on the lifts). Every one of them flickered upon impact with the brass mallet. He then asked what would happen if I hit a new or good module really hard. I asked if he would be willing to install a new module on the 78 Fairmont in case a hard strike would damage the module and cause the customer problems down the road. He authorized a new module on the 78 Fairmont. So, on the original module on the Fairmont I hooked the scope back up and hit the module progressively harder. No flickering. I then belted it hard. No flicker. I then got my BFH (big 3 lb ball peen hammer) and hit it really hard. No flicker. I then replaced the now dinged module (from the iron hammer, not the brass mallet) with a new unit. He was convinced.

After going back to Michigan he shared his findings with some engineers, and they ultimately agreed my technique was a useful and effective approach in diagnosing bad modules. The next Ford Technical Service Bulletin (TSB) included my technique, but Lee Sanders put his own name on the article, as opposed to giving me credit for devising that technique. He probably got a nice bonus for a significant cost saving technique being published.

Anyway, not to needlessly belabor things in my past... I guess the point is I am not afraid of electronic ignition or electronic engine control systems, especially when I have my trusty hammer in hand! heh heh... And, I will concede electronic ignition systems offer some really nice advantages over older Point and Condenser primary ignition systems. But, for run of the mill cars driven on public roads (not raced on a track) a Point and Condenser ignition system can be set up to run more than plenty well. "Set up how," you ask? First set the initial point gap, then set the dwell angle for a more precise gap setting. Use a very thin amount of distributor point lubrication on the point cam lobes to keep the the rubbing block in the points assembly from wearing down too soon. And replace the points every 12,000 - 15,000 miles. Other than the arcing eventually necessitating replacement of the points, the old electro-mechanical points and condenser systems were plenty reliable. At really high RPMs we would get "point bounce." Dual Point distributors helped remedy that. But, the electronic ignition systems did help in those situations even better. And they helped manufacturers to move slowly into computer controlled engines over the years, a definite gain for us all.

For me, if any of our vintage cars came from the manufacturer with Points and Condenser, I will just keep using old school technology as it is more than good enough. That goes double for our 1969 Shelby GT500, as I want to keep that vehicle pure stock. And I will check my dwell angle once in a while just to make sure the points are not closing up due to the rubbing block wearing (despite being properly lubricated). For later engines with electronic ignition I will keep using their tried and true solutions, as later electronic (module) manufacturing techniques provided us ultra-reliable parts, at long last. Our 73 Mach 1 had a nice MSD distributor and 6A module when we purchased it 4 years ago. I kept the MSD system in it untouched for a year. Then I replaced the 6A module with a 6AL as I wanted the Rev Limiter feature. It was a direct plug and play swap of the two modules. But, I kept the 6A module in case the 6AL ever did fail, I now have a backup unit!

All that having been said, were I to replace a Points and Condenser system, or an aftermarket electronic ignition system with anything, it would likely be a Pertronix solution. But, I would likely get a spare system in case I ever had a problem and ran into an ignition problem. I would not want to use my brass mallet to test one of those systems, heh heh...
 
A word of caution. The Pertronix module is only supported in stock Ford distributors. The issue is with the dimensions of the cam in aftermarket points distributors.
Very true. I tried to install the Petronix II on my 429 SCJ, but it did not fit due to the replacement distributor. Petronix only works with OEM equipment.
 
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