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Mon Sep 08, 2008 4:04 pm

i have a 3 ohm coil. will a 1.5 ohm ballast resistor allow this coil to be compatible with a mallory unilite distributor. thanks

Mon Sep 08, 2008 10:36 pm

rob69tam wrote: i have a 3 ohm coil. will a 1.5 ohm ballast resistor allow this coil to be compatible with a mallory unilite distributor. thanks
You can run your 3 ohm ignition coil with a Mallory Unilite distributor as is.

The 1.4 ohm spec is the MINIMUM ballast resistance that the Mallory ignition coil can drive without damage.

However, you would have better performance with an ignition coil with less total ballast resistance. You would also have much better performance using an Air Gapped Core ignition coil such as those made by Jacobs. Most Jacobs ignition coils have a primary resistance of about 0.4 ohms, so they would require that a 1.0 ohm ballast resistor is connected between the Positive terminal of the ignition coil and +12 Volts, so that the total ballast resistance is at least 1.4 ohms.

Scott Novak

Tue Sep 09, 2008 3:57 am

thanks scott

Mon Feb 27, 2017 3:33 am

Do you need a ballast resistor if your running CDI (I.e a hyfire 6al) into a unilite?

Mon Feb 27, 2017 8:13 am

Hustlers67 wrote: Do you need a ballast resistor if your running CDI (I.e a hyfire 6al) into a unilite?

Dont understand what you mean "into a unilite"... I believe the The unilite is the distributor and it triggers the CDI system that is firing the coil.... A ballast resistor may or may not be used on coil depending on coil... You need to look at tech specifications of the "box", I know the MSD 6 series does not require a ballast resistor but it also states "if there is one on the vehicle you can use it"..

Dont know if this is correct instruction sheet for your CDI box but it may help...

http://documents.holley.com/mallory_instructions_h...m_0001.pdf

See note on page 1 about coils...

Dale

Tue Feb 28, 2017 7:37 pm

Thanks Dale, yes I didnt explain that very well at all.

I have the Mallory Unilite distributor, triggering a Hyfire 6AL2 which will then fire the Mallory coil (pn 29216). The coil itself doesnt have details of the resistance, however a google search indicates that:

Primary resistance is: 0.700 ohms and
Secondary resistance is: 8.9k ohms

My concern here is the notes to this coil, which says:

"Notes: Not compatible with aftermarket capacitive discharge (CD) or high energy inductive ignition systems. Will not work on fuel injected vehicles. Not for fuel injected vehicles. Includes replacement boot for coil wire."

I picked up the coil and unilite at the same time, then lucked upon the hyfire later.

... I think I need another coil. Any suggestions?

Tue Feb 28, 2017 8:10 pm

Probably any 3(+/-) ohm standard ignition coil will work....

If 'box' was MSD, there is a list of about 75+ coils that will work...For the Mallory, I am not sure..

Dale

Thu Mar 02, 2017 6:58 pm

I use the Mallory unilite distributor and CDI coil with Hyfire box. I'm not using a ballast resistor for over10 years. Never had problems with ignition to 7k.

Thu Mar 02, 2017 8:02 pm

Which coil Deho?

I am going to check the coil I have (Mallory pn 29216) to see the actual resistance. A receipt I have shows it was catalogued in the vendor's system as "0.7 ohm resistance and CDI compatible" ...
(despite the sticker on the coil)

As I am understanding it, i need a low resistance coil for the CDI box and Unilite. 3.0 ohm coils being suitable for points, or a more stock setup. - tell me if I have this wrong!! :oops:

If the Mallory coil is no good, I am tossing up getting one of the following:
- Pertronix flame thrower III (.32ohm), or
- Accel super stock - breakerless electronic coil - 8145 - (0.7ohm)

.. i am sure there are many more.