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> History Repeats Itself.... Ignition Question, Coil Overheats, Have Mallory, What's best solution
DrinkMan
post Jul 11 2019, 04:04 PM
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A couple of nights ago, we were taking the 914 out for an evening drive to dinner. It didn't feel quite right and there were more backfires than normal (we are used to a few burbles under decel) and all of a sudden, it just died about 8 miles from home. We were unable to restart the car and were getting no spark.

We decided to sleep on it. I researched the history of the car from the previous owner here (he did a great job documenting his activities) and found this was not the first time with these symptoms.

Overheat Coil

No Spark

So, the next morning, before troubleshooting, we tried to start the car and it started fine. After just about 2 minutes of running (pulling it out of the garage and turning it around to put it into a more service friendly position), I shut it down. The coil felt pretty warm to the touch. Looks like we had an overheating coil (yellow Accel 8140 with external ballast resistor giving a total resistance of about 3 ohms). I replaced the coil with another 3 ohm coil I had laying around without the ballast resistor.

While we were at it, we cleaned the contacts in the distributor cap and rotor (Mallory 45xxxxx, same as mentioned in the thread above). Now, with the new coil, we restarted the yellow beast. Wow, not only did it fire up faster than ever, but on our test drive, all the backfires were gone and the performance was the best we have ever experienced in our 2 years of ownership.

All this background is leading up to my question - I noted that our car's Previous Owner (not Dreaded Previous Owner, but Great Previous Owner) had to replace his Mallory at one point. Mallory is no longer available and my question is - what is the right solution if I want to replace the ignition system? (2056 with dual Weber 40's)

I have a Compu-Fire DIS ignition system on our Opel and love it. It was originally designed for VW and the Opel used the same Bosch distributor and works well on it. However, my research here on 914World does not show it as a very popular option (advance curves on Bosch 009 not great for 2056?). And on the same track, if the 009 advance curves for Compu-Fire aren't great, wouldn't that mean the Pertronix is also not the desired solution?

I hope this question is not as bad as asking what is the right oil type (I'll never ask that on a forum, I know better) as I assume there may be some difference of opinion on best ignition solution for a 914. The 123 system is tempting but my search did not see it as a preferred system.

Thoughts? (btw, I'm a little reluctant to drive the 914 great distances for a while. My wife suggested I buy a pair of epoxy filled 3 ohm coils and carry with us as spares)



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tejon007
post Jul 11 2019, 07:42 PM
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"I replaced the coil with another 3 ohm coil I had laying around without the ballast resistor. "

Generally, the Mallory Unilite uses a ballast resistor (or loom resistance). If you run without one, you're eventually going to destroy the ignition module. The ballast resistor is to reduce the current flowing through the coil. You'll also need to measure the resistance of your coil.

The Unilite is a great distributor and have used them for a long time. But, you should download instructions from Mallory and make sure you set up the ignition system correctly, including the correct coil and ballast resistor (there's also one from Mallory) is the correct one and everything is wired correctly (i.e. you can destroy the ignition module if you get it backwards)...

Only problem is that parts are getting hard to come by...I've stockpiled things like ignition modules and caps.

IMHO, keep the Unilite, it's a good fit for your 2056...
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jim_hoyland
post Jul 11 2019, 08:06 PM
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I used the Mallory Unilite for 10 years. Try replacing the distributers optical Sensor first. You do keep a spare ? And, install a Bosch blue coil with the new sensor.
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ChrisFoley
post Jul 12 2019, 07:50 AM
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We noticed that quite a few oil filled coils didn't handle the heat well when connected to a Mallory Unilite with the engine idling in the driveway for a while.
Epoxy filled coils didn't have the same problem.
Bosch Blue coils seemed to work fine.
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tejon007
post Jul 12 2019, 11:38 AM
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How about a Mallory ProMaster coil, Mallory ballast resistor & combine it with a HyFire CD ignition? (It comes with a rev limiter)

This would be a great combination for the 2056...then set your distributor curve where you like it.
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DrinkMan
post Jul 12 2019, 04:33 PM
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QUOTE(tejon007 @ Jul 11 2019, 09:42 PM) *

"I replaced the coil with another 3 ohm coil I had laying around without the ballast resistor. "

Generally, the Mallory Unilite uses a ballast resistor (or loom resistance). If you run without one, you're eventually going to destroy the ignition module. The ballast resistor is to reduce the current flowing through the coil. You'll also need to measure the resistance of your coil.

The Unilite is a great distributor and have used them for a long time. But, you should download instructions from Mallory and make sure you set up the ignition system correctly, including the correct coil and ballast resistor (there's also one from Mallory) is the correct one and everything is wired correctly (i.e. you can destroy the ignition module if you get it backwards)...

Only problem is that parts are getting hard to come by...I've stockpiled things like ignition modules and caps.

IMHO, keep the Unilite, it's a good fit for your 2056...


Thanks for the input. I'll go download the instructions and study them. The Unilite has been in there for years. The Previous Owner did a thread on his adventures with it and I've not touched it until the coil overheated (perhaps too much load due to cap and rotor wear/scorch). But one question I have - what is the difference between a Coil + Resistor with 3 ohms total vs a 3 ohm coil? Same current. I'll be glad to get a epoxy coil and resistor combo with total load that is the same.
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DrinkMan
post Jul 12 2019, 04:37 PM
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QUOTE(ChrisFoley @ Jul 12 2019, 09:50 AM) *

We noticed that quite a few oil filled coils didn't handle the heat well when connected to a Mallory Unilite with the engine idling in the driveway for a while.
Epoxy filled coils didn't have the same problem.
Bosch Blue coils seemed to work fine.


I'm a fan of epoxy coils as well. I don't idle in the driveway much, tend to just take it easy until warmed up. We even have a test lap of a couple of miles that we always drive our old cars before heading out (the lap is within "walk home and get a tow car to bring it home" distance). The night of the coil failure, we pulled out, took the test lap, made the decision to go and struck out.

Do you recommend a coil + resistor or a coil with resistance = to the coil plus resistor?
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IronHillRestorations
post Jul 12 2019, 05:38 PM
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Where/how is the coil mounted? Some of these ignition components are designed for US cars that mount the coil vertically. I know the MSD oil filled coils should be mounted vertically, they only recommend epoxy filled for other mounting orientations.
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DrinkMan
post Jul 12 2019, 08:52 PM
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QUOTE(IronHillRestorations @ Jul 12 2019, 07:38 PM) *

Where/how is the coil mounted? Some of these ignition components are designed for US cars that mount the coil vertically. I know the MSD oil filled coils should be mounted vertically, they only recommend epoxy filled for other mounting orientations.


I agree with you. Another reason to go to epoxy, the coil is horizontal. I've always believed that oil cooled need to be vertical. I have an epoxy coil on the way (thank you Amazon).
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