Mallory Unilite...Use, upgrade or buy different brand?

[MickMc]

My current set up has a Unilite with tach drive. I like the tach drive but don't use it, so I was considering upgrading to MSD or something better, more spark etc.
The current combo is a big block Chevy with a four speed, street and strip driven with a carb.
OK lets here the ideas guys.
Mick Mc

[rocketman]

i prefer msd.there proably the best out there.

[Bad Bowtie]

Mick,
I'd go MSD also. I've had no problems with them in all the years and cars I used them on. I've also used some Unilite stuff but feel the modules are too sensitive to voltage changes and have burn out a few modules @ 80-90 dollars a pop (even with the ballast resistor installed.) I think you'll find most people use MSD stuff. Good Luck
Jack

[PRO TC]

MSD BABY!!! my dad bought a mallory unilite dist and coil at a swap meet for 50 bucks i used it in my big block before i went to msd, now its in his smallblock 36 ply. one thing i did notice with the msd the car starts and idles way better. but still working for him.
barry

[MickMc]

Thanks for the response.
It looks like the Mallory is going to Egay.
A MSD E curve is on the horizon, and maybe a Digital box.
Time to clean out the extra parts and send um to Egay.
Mick

[Cheatin'Chad]

You can only use as much spark as you need. If it fires properly under all the conditions you use it in there is no reason to upgrade due to "power".
If you would like the Multiple Spark Discharge (MSD) at around 3,000 RPM and below as well as the ability to schoose rev llimits and retard for boost/nitrous then a MSD brand set-up or equivalent would be something to consider.

[6'9"Witha69]

In my experience, the unilite pickup goes bad quite frequently! Go with MSD.

[andrewb70]

Ide run it till the unilite pick up goes bad. There is nothing worse than getting a $250 dollar part, installing it, and not having a bit of difference. Thats how it will be when you install the MSD assuming the Unilite is working properly.

Andrew

[Martin71RS]

I will be running a Unilite since it came with my motor, previous owner raced street machine and was Dutch champion with it twice.....can't be that bad then....this is some info I found on the net:


The Mallory Unilite® Module is a highly accurate, reliable and simple ignition trigger and amplifier. The self-contained Unilite® Module consists of an integrated photo coupler, a signal processor, and a power switch. Every time the special shutter wheel rotor stops the infrared light from reaching the photo coupler, the electronic circuitry energizes the ignition coil. When the shutter wheel allows the infrared light to reach the photo coupler, the electronic circuitry allows the stored energy in the ignition coil to discharge to the spark plugs. No adjustments are ever necessary.
One of the statements we hear almost every time there is a Unilite® module failure is that it is a P.O.S. that cannot handle abuse. Well, can anything handle abuse? The Unilite® module is as reliable as the high-end stereo amps in many vehicles, the ECM in computer-controlled vehicles, and any other electronic ignition module design on the market. (They just don't offer you this information, but we at Century Performance Center do) Why do they at times fail? That is easy and described below, but simply put, it is either owner error (usually lack of correct information or installation), or something wrong in the vehicle's electrical system (starter, alternator, etc). In other words, STOP blaming the module and find the real problem! Repeated module failures are notifying you of other issues.
ALL of the Mallory Unilite® modules are part number MAL-605.

Testing the Unilite® Module (distributor in engine test procedure)


NOTE: "If you are using a CD (capacitive discharge) Ignition Box (Mallory Hyfire®, MSD, Jacobs, etc ... you must first bypass the box before performing this test." To bypass the box you will need to install the bypass connector (Mallory Hyfire units), or un-wire other brands.

Step 1) Remove the distributor cap and rotor (some rotors are on VERY tight). Turn the ignition ON and test the voltage at the NEGATIVE side of the ignition coil using a DMM (Digital Multi-Meter) by connecting the black lead to a good ground, and the red lead the negative post on the ignition coil. At this point the voltage should read 12-Volts.
Step 2) If battery voltage is present, place a credit card, driver's license, business card, or other similar object and block the photo optic of the module (this is between the eyes on the module). The voltage should now drop to read only 1-2 volts. When you remove the card, the voltage should return to battery voltage. If the module passes this test, it is working correctly.
Step 3) If the results are as stated below:
If the voltage does NOT drop, this means that the module is "open" and must be replaced. This may have been caused by a power surge, high resistance in the plugs or plug wires, or an improper ground. A charging system dump can also cause this. (that means that the alternator is dumping voltage and usually hits ground)
Voltage always stays below 3.0 Volts. This means that the module has been spiked by high voltage or amperage, the lack of a ballast resistor, or it was improperly wired.
If the voltage only drops 3-4 volts this will cause a weak spark.
Possible causes include:
Faulty charging system (stuck or shorted regulator/alternator)
Faulty starting system (excessive starter drag, not enough voltage getting to the starter, worn brushes/armature)
Non-suppression style spark plug wires are being used (Solid copper or Stainless core wires). You MUST use spark plug wires that are carbon core, or the better spiral core design.
Too large of an amperage output alternator being used.
Ineffective or inadequate vehicle grounds
High Amp Stereo Equipment (typically not adequate grounds or power supplies to the amps).
CB Radio spiking on mic click into electrical system (typically only power modified CB radios)
Direct shorts in the ignition or vehicle electrical system
Trying to start the engine with a battery charger or booster/charger hooked up. (power spikes as well as too much amperage)
Welding on the vehicle with the distributor hooked up (disconnect the 3-wire plug at the distributor before welding)
Faulty, dirty, or improper grounding of the Unilite® module.

What does this mean in simple terms?
You MUST have the correct ballast resistor (Mallory part #MAL-700, other brand resistor, or resistance wire) installed on the "POSITIVE" lead to the coil. The "trigger side" (green wire) of the Mallory Unilite® module does not operate at a full 12-volts. You need 8-9 volts "maximum" supplied to the trigger side of the module. Too much voltage will kill the module. Even though the ballast is wired in on the positive side of the coil, it is actually dropping the voltage on the trigger side (negative side of the coil) Wiring Details. The positive side of the module can handle 14+ volts.
NOTE: When using a Mallory Hyfire® series ignition control (or other comparable brand) you do not absolutely need the ballast ... though, if you ever were to have a problem with the ignition control unit, you can easily bypass the ignition unit and still race using just the Unilite® distributor. Without a ballast resistor in place you will have to add one before running the engine without the ignition control unit.
Anytime you do *anything* electrical on the vehicle ... I do not care whether you are charging the battery, changing the alternator, the starter, or anything at all on the car ... DISCONNECT the 3-wire connector from the distributor. This will guarantee you do not spike the Unilite® module. If you do not want to take a chance at spiking the module, this is the best way. Remember, it is not the module that is dying on its own, it is some other component (or human) that is causing the failure. You just want to make sure that nothing bad happens to your module.
NEVER, I mean NEVER ever try to "boost" start your engine by using one of the start/charge battery chargers on your vehicle equipped with a Unilite® module. As mentioned above your module only requires 8-9 volts and voltage levels above that (especially the high Amps) means you take the chance of damaging the module. Fully charge the battery (with the Unilite® Distributor 3-wire connector disconnected) and then disconnect the battery charger, reconnect 3-wire connector and start vehicle. If you own a computer-controlled late model vehicle, this is the same procedure recommended by the vehicle manufacturers to prevent ECM damage.
If you want some added protection (but not a guarantee) from *supply-side* power spikes hurting your module, install a Mallory Active Power Filter (part #MAL-29351) inline before the module. This is a recommended, but not required procedure to all Unilite® users. See below You can also install what is called the Power Cell to use as a buffer between the grounds on the vehicle and the trigger side of the module. The Power Cell is basically a tough capacitor that filters (and blocks) all spikes coming up the ground side of the electrical system.
It is also recommended with *ANY* electronic module ... not Just Mallory ... to have a spare module on hand in case of failure. This is the same with the GM HEI, the Ford Ignition Module, or any others. Yeah, we know the module is nearly one hundred dollars, but how much is a tow bill or the stress from having your family stranded. And "NO, the Mallory Unilite® Module is not more (or less) sensitive than the factory GM HEI, Ford, or any other brand electronic ignition module." Having a spare module is just good common sense.
You may not know this ... the Mallory Unilite® module is also an ignition amplifier as well as the ignition trigger. If you use a high power ignition unit (such as the Mallory Hyfire®, MSD, Crane, or other ignition units) and if you happen to ever have a failure of the ignition unit, you can easily bypass the ignition unit and operate the vehicle with just the Unilite® distributor. (you must have the ballast resistor installed to do the bypass).
You must use the correct coil when using a Mallory Unilite® distributor. There are many brands of coils available, but we must recommend the Mallory Promaster series of coils. Part #MAL-29440 is the most popular and includes the ballast resistor as well as the coil mounting bracket. This is one great coil! A new Mallory Promaster coil is now available (#MAL-29450) that is internally resisted, but you CANNOT use this coil with amplifier units (Hyfire, MSD, etc).
Plug Wires: Any ignition system (besides magnetos) requires some amount of resistance in the secondary ignition system (spark plug wires and spark plugs). Where too much resistance (tested with an Ohm meter) can cause problems, so can too little. The coil needs resistance on the secondary side to properly build and release voltage. You should also know that the greater the plug wire length, the higher the resistance. Spark plug wire is rated in "Ohms per foot".

Eliminating power spikes and electrical system problems. (Mallory Power Cell, and Mallory Active Power Filter)
In many instances it is your own electrical system that causes damage to your Mallory Ignition System components. A sticking diode in the alternator or a bad regulator, bad or under-rated grounds (engine, chassis, body), sloppy wiring, and more can cause damage to other electrical system components.
If you understand the causes of problems you can work on making sure that you limit ignition electrical system failures. Knowledge is key, and that is your best tool.
Using a Inline Fuse with your ignition control: (Mallory HyFire®, etc)
A protection factor that you can do though to protect your aftermarket ignition units -- consider it Insurance -- is to add an inline fuse on the RED power lead into your Mallory Hyfire®or other aftermarket ignition unit. The fuse rating should be over the 1 Amp per 1,000 RPM draw of the unit based on engine operating speed. This is the wire that connects directly to the battery or 12-volt power supply. The fuse will cushion minor voltage and amperage variances, or the fuse will blow if there is a serious deviance in supply voltage, thereby protecting your ignition control unit. (This is funny that the ignition unit manufacturers do not tell you this, or even include a fuse in the power supply lead isn't it?) The reason you are not told this information is that the demand of the ignition unit varies under loads and RPM changes. You do not want to undervalue the fuse rating and lose needed power supply to the unit.
An Example:
You have a nice engine that sees 6500 RPM shift points --- add a 10-20 Amp fuse (1-Amp times 6500 RPM is a 6.5 Amp fuse, but give yourself a bit of room). The reason for this rating is that your ignition unit will normally draw just under 1-Amp per 1000 RPM, but it will rise under load and requirement. If you add a 6.5 Amp fuse on a 6500 RPM engine you may blow the fuse every time you get to your shift RPM, or lose needed supply voltage to the ignition unit when the fuse heats up from supply voltage.
Using the Mallory Active Power Filter:
If you want to protect the supply side of your Unilite® module on your vehicle you
can install a Mallory Active Power Filter (part #MAL-29351) to protect against minor positive side problems.
The Active Power Filter is designed for Mallory Unilite® Systems that experience failures with the ignition modules from minor voltage spikes (voltage transients, power surges). Voltage spikes are associated with "noisy" electrical systems from electrical defects such as worn or dirty alternator brushes, corroded or oxidized electrical connections and similar electrical problems. Voltage spikes are clamped and regulated by the Active Power Filter from damaging theUnilite® Ignition Module. The Active Power Filter connects between the distributor female connector and the distributor wire harness male connector and attaches easily to the distributor with an included Velcro® strip.
NOTE: This NOT a guarantee of spike protection ... just insurance in a device that can handle simple electrical problems on your vehicle. Hence, the term "filter".
Using the Mallory Power Cell:
The Mallory Power Cell (part #MAL-611) is most known for it's ability to slightly amplify coil output on factory ignition coils. The essence of the Power Cell is a that it is a large capacitor that stores energy for release upon each spark cycle, but in our case here, we will use the Power Cell to absorb voltage feedback that occurs on the negative side of your vehicle's electrical system. Feedback occurs when most often when using a generator instead of an alternator, but it also occurs when you have electrical components dumping voltage that enters the ground (negative) side of your electrical system (common with one-wire alternators). This occurs from starters with worn armatures, alternators/regulators that sometimes kick out a voltage spike upon "ignition off" after the engine is running, hooking and un-hooking battery cables (ground cable), and more.
NOTE: This is still not going to protect your ignition module if you are ignorant enough to weld on your vehicle with the distributor and other critical devices connected, but is very tough and blocks most all negative side spikes.
To see how to wire in the Power Cell for module protection, click here.

[Cheatin'Chad]

I ran a Unilite distributor in my '78 Malibu for two years and then sold the car. It's still working fine 3 years after the sale.

[cad]

Ide run it till the unilite pick up goes bad. There is nothing worse than getting a $250 dollar part, installing it, and not having a bit of difference. Thats how it will be when you install the MSD assuming the Unilite is working properly.

Andrew

I also ran a unilite for 12 years before it needed a rebuild. Sent it to Mallory to have the advance mechanism rebuilt. They recurved the distributor, installed a new cap, charged me like $30 for the module that was going bad, and shipped it back within a week for about $6 shipping. Good folks.
Then, I thought I was having an issue with it, still, so I bought the whole MSD billet, 6al, and blaster SS coil. Made maybe a .10th in the eight mile, tops, and that could have been the weather.
Run the unilite if you still have it. Sure the MSD looks cool, but you'll have to drill 4 new holes to mount the box...

[David Pozzi]

I was at an autocross and saw a unilite module fail in a competetors car he had it towed home. I bought a unilite for my race car because I wanted electronic ignition and didn't have extra space for an ignition box, the unilite failed the advance mechanisim after 4 hrs use, I was reving to 7000 rpm's. The advance weights were made out of pot metal! The spring anchor pins are just pressed into the pot metal weights and worked loose allowing the weights to jam against the housing, it spun around twisting the tach cable.

It might be OK if you carry a spare module with you and don't rev a lot, maybe later distributors have different advance weights now.

[MickMc]

Dave and every one who replied

[MickMc]

Dave and every one who replied Thanks

I found a guy who rebuilds distributors for all make and models...
Anyway this guy rebuilds distributors with HEI modules either mounted to the distributor or remote mounted. He said he can convert my Mallory to HEI. This would give me ease of replacement if a failure occured somewhere and no ballast needed. My only hurdle now is that I HATE the cap on the Mallory and I would prefer a cap that uses HEI style wire ends (MSD makes a 'cap-adapt' for Chevrolet style caps).
I found this company "Davessmallbodyheis.com" while I was trying to upgrade my 64 Coupe de ville to electronic ignition. Most guys think that the Pertronix is the way to go but I disagree and Dave had the data and alternative to prove it.
I am trying to get Dave to make me a deal on converting the Cadillac distributor and the Mallory at the same time.
I'll post more as things progress.

Mick Mc

[David Pozzi]

Dave's setup is well known and most guys are very happy with it. The advantage is the module is a very common one and easy to replace.

[MickMc]

All this time I thought I found something that not to many people knew about.
I guess its hard to find something new in this crowd.
The Cadillac is getting a Dave unit for sure, a kind of stealth HEI in an old Cadillac. That should go well with the battery in the trunk, internal regulated alternator and closed cooling system.
Sometimes it's the little details that I like the best.
Mick Mc

[LowBuckX]

I built my own dist just like daves small body hei for about $40 and some lathe time.

[Colin Frolick]

i've had a unilite on my pontiac for about 7 years and have not had any problems, except for the vacuum advance diaphragm failing once.

[LS6 Tommy]

I'm glad to hear people are having good luck with the Unilites. I have never seen one last for more than about 1000 miles on street driven cars. I've also seen a lot of them only go about 300 miles or even less.

Tommy

[HILROD]

The Unilites need to be wired right, with a balast resistor and good engine ground to live. A friend started his car with the front fenders off, [and ground wires],and popped the module right away. Since it had been running fine he started replacing everything but the distributor. They work O.K., just keep a spare module around. FRANK