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Old 11-07-2019, 02:04 PM   #1
joe dirt
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mallory unilite system

new to me truck with 383 stroker has a unilite distributor and coil, ive been reading where you need to have a ballast inline, but mine does not have a ballast, previous owner said its been like this for years, can this hurt things?

reason for me looking into this is because every once in a while after I first start the truck it will shut off almost like the key was turned off, but it will fire back up and be just fine

also noticed the tach seems to work fine under 2k rpms...but does not want to go much above that, and does not seem that accurate even at those lower rpms
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Old 11-07-2019, 03:10 PM   #2
GASoline71
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Re: mallory unilite system

I had the exact same setup 100 years ago, in an El Camino... you need the ballast resistor. Trust me. The Unilite comes with a ballast resistor in the box when you buy it new.

Gary
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Old 11-07-2019, 03:34 PM   #3
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Re: mallory unilite system

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Originally Posted by GASoline71 View Post
I had the exact same setup 100 years ago, in an El Camino... you need the ballast resistor. Trust me. The Unilite comes with a ballast resistor in the box when you buy it new.

Gary

do you think that's whats causing my issues?...ive also read that they don't normally random work or not...ive read they either work or they don't


im half tempted to pull it all out and drop in an hei unit...except the truck runs really good and the power is great as it is now...
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Old 11-07-2019, 04:25 PM   #4
GASoline71
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Re: mallory unilite system

Could be what is making your ignition act weird. Mallory ain't what they used to be. Quality has slipped a lot over the years. I ditched the setup for an all MSD system when the car went drag racing for 10 years.

Personally, I'd find a good GM HEI and have it rebuilt and tuned. I'd steer clear of the 50 dollar Made in China HEI's. But that's just me.

Gary
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My 1972 GMC 1500 Super Custom (Creeping Death) "long term" build thread.

The Rebuild of Creeping Death after the wreck

Quote:
Originally Posted by LONGHAIR View Post
I would never rebuild a 305.
Quote:
Originally Posted by prostreetC-10 View Post
I love using vacuum gauges as part of the carb tuning process. I hook the gauge to the inside of my garbage can and leave it there.
Quote:
Originally Posted by Marv D View Post
Remember Murphys 2nd law of mechanical relationships... "OPPOSING COMPONENTS ATTEMPTING TO OCCUPY THE SAME SPACE, AT THE SAME TIME, GENERALLY END UP OCCUPYING ADJOINING SPACE AT THE BOTTOM OF THE OIL PAN"
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Its cheaper to listen to advice given when you ask for help than it is to ignore everyone and wait for carnage.
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Old 11-07-2019, 04:36 PM   #5
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Re: mallory unilite system

that yeller thing on the left there <-- ran best et of 11.7 with unilite, hyfire box, and a promaster coil

can't see the rest of the goodies, but that big ol block resister is hanging up there right of the remote solenoid



I loved its simplicity, ease of adjustment with a simple step key, and massive reliable and consistent ignition power..

I would lean towards following the manufacturers directions for installation over previous owner testimony..

but you also should check that wire to make sure it isn't resisted elsewhere, maybe even unbeknownst to the previous owner, before adding a resistor..

and also verify your grounds, clean and present where they ought to be..

good luck, but if you decide to ditch it, please offer to me first to buy it from you


https://documents.holley.com/mallory...7_38_45_47.pdf

Quote:
NOTE: The purpose of an ignition ballast resistor between the ignition switch (12V) and the ignition coil positive terminal is to restrict current flow through the ignition coil. Failure to use an ignition ballast resistor will eventually destroy the Ignition Module
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Old 11-07-2019, 04:38 PM   #6
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Re: mallory unilite system

I’d swap to hei too.
Here’s one of the better ones.

https://performancedistributors.com/
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Old 11-07-2019, 06:09 PM   #7
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Re: mallory unilite system

I have used the unilite in my 69 GMC for about 20 years with no problems. I didn't add a balast resistor.
I just used the resistor wiring that is already in the harness for the point type distributor.
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Old 11-07-2019, 06:10 PM   #8
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Re: mallory unilite system

Quote:
Originally Posted by Killer Bee View Post
that yeller thing on the left there <-- ran best et of 11.7 with unilite, hyfire box, and a promaster coil



but you also should check that wire to make sure it isn't resisted elsewhere, maybe even unbeknownst to the previous owner, before adding a resistor..



https://documents.holley.com/mallory...7_38_45_47.pdf

im starting to think it must be resisted somewhere,..i know I don't have the ballast that was supposed to come with it,..truck is a 64 so maybe they used the factory resister wire?...im not really sure what to look for when trying to find that wire

I say this because I just read up a lot on it and from I see most people that don't have it resisted, blow up the led bulb within 3 starts with the key...mine has been starting for years supposedly,..myself personally have started it atleast 100 times since ive owned the truck
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Old 11-07-2019, 09:32 PM   #9
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Re: mallory unilite system

I reread your symptoms and it's making me think it could be weak ground or poor connection somewhere.. intermittent symptoms are the most challenging but I wouldn't throw the baby out with the bathwater I think it's worthy of a good diag or else you may be chasing it endlessly regardless of distributor type..

as for the resisted ignition wire, perhaps ballast resistors carry more stable current than what a factory coil needed? or it's deteriorated, degraded or failing in some manner?

could be worth a shot to grab a ballast resister and mock up a new circuit direct from b+ to see if the symptoms change/go away.. I would also suggest clean and confirm all connections, grounds etc.. could be all the way back in the key switch..

check the pickup coil to see if it's clean and clear where the shutter breaks the light beam.. I don't recall ever having an issue there but age, dirt, dust, etc in a truck environment may have migrated in there creating intermittent failure..

I have never called so not sure what you'll get but possibly call their tech line and see if they can shed some light on it (pun intended ) especially about the tach issue, that's got me puzzled.. I ran a 5" autometer without any glitches in my goat..

good luck and please keep us posted.. I have long range plans to repower my k20 burb with a 383 and the hei on the 350 in there now is riding the firewall due to my past experience, I was considering a unilite or similar compact distributor and I am very interested in your findings, thank you!
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Old 01-20-2020, 03:03 PM   #10
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Re: mallory unilite system

Quote:
Originally Posted by Killer Bee View Post
that yeller thing on the left there <-- ran best et of 11.7 with unilite, hyfire box, and a promaster coil

can't see the rest of the goodies, but that big ol block resister is hanging up there right of the remote solenoid



I loved its simplicity, ease of adjustment with a simple step key, and massive reliable and consistent ignition power..

I would lean towards following the manufacturers directions for installation over previous owner testimony..

but you also should check that wire to make sure it isn't resisted elsewhere, maybe even unbeknownst to the previous owner, before adding a resistor..

and also verify your grounds, clean and present where they ought to be..

good luck, but if you decide to ditch it, please offer to me first to buy it from you


https://documents.holley.com/mallory...7_38_45_47.pdf


I replaced the whole system with msd, but after the fact I realized my problems were the factory resistor wire was faulty, but owell...I am currently selling the complete system if your interested, theres a new post in the misc for sale section
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Old 01-20-2020, 11:43 PM   #11
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Re: mallory unilite system

thanks for posting the lead here, replied to your sale thread!
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