Mallory ignition questions, Partial success! Options

[VaccaRabite]

My carbed 2056 uses a Mallory Unilite ignition. All summer long I have been fighting intermitant misses leading to the motor dieing at idle. After dicking with the carbs and adding fresh spark plugs, I am now moving to ignition.

So here is how my system is set up.

Bosch blue coil.
Mallory Unilite ignition.
The ignition is behind a resistor block.
MSD spiral wound plug wires.
NKG b5es plugs pregapped (one heat range hotter then stock as suggested in the resent spark plug thread) .

My tach is not dancing when I have a miss. The idle indicated drops as expected, no drama. So I don't think that the coil is grounding out or arcing.

As I understand the Mallory dizzy, it either works or it does not work, and there is not a lot of in-between.

My primary suspects are the plug wires. I am using the MSD spiral wound wires suggested for use with the Mallory, and I have only been using them this season.

Since you are not supposed to use the regular plug wires with a Mallory (as they can somehow cause the optical unit to burn out) buying replacement wires on a hunch is kinda expensive. Am I chasing my tail with this?

Also, I am using the stock gap. I think I am supposed to be able to use a wider gap with the Mallory, which will give better ignition. What kind of gap should I be shooting for? If it does turn out to be the plug wires as the problem area, should I go back to the stock heat range plugs, or stay with the hotter ranged plugs?

Oh, and for the "go back to FI" crowd, my motor is using a cam that would cause D Jet to commit suicide. In this case, it is not an option.

Zach

[jaxdream]

Running the stock gap you probably ok on , I'd stick with the hotter plugs. You didn't list a MSD unit or similar box, you could check the plug wires using a good multimeter also the coil for spec, find out the specific ohms per foot of the subject wires . Hook each one up to the meter to see if the wire specs out, wiggle them around and such to see if the is a possible break in one of em, check your resistor also . I can't say much about the Mallory dizz , no experience with them. Good luck , as ignitions can make ya crazy .....

Jack / Jaxdream

[zx-niner]

When you say the ignition is behind a resistor block are you referring to the resistor that Mallory shows in line with the positive coil junction for coils that do not have the proper internal resistance? I've been told the Bosch blue coil has adequate internal resistance and does not need the additional ballast resistor.

[orange914]

When you say the ignition is behind a resistor block are you referring to the resistor that Mallory shows in line with the positive coil junction for coils that do not have the proper internal resistance? I've been told the Bosch blue coil has adequate internal resistance and does not need the additional ballast resistor.

i just went through this with the coil resistance for a pertronix (IF mallory has the same requirement). IT required 2.5 to 3.0 ohm resistance. the mallery blaster only has 0.7 so a resister was needed. we ended up using a new stock ford (points) coil. it had 2.5 ohms, so no additional resister.
the pertronix guy DID say they see weird intermittant issues (not just run/no run) when a needed resister is not run. again may or may not relate to mallory
F.Y.I. local flaps carries 77 chrysler van 318 ballest resister was 1.8 ohms and chevy had one @ 2.5 ohms .

[FourBlades]

I am running mallory dist (with circuit guard box), mallory wires, blue coil, and normal
heat range plugs on my 2270. No resistor. Runs and idles well once warmed up.

John

[Gint]

Stock gap since you didn't really increase the spark. I don't know nothin about having to use Mallory wires. I have stock-ish wires on mine and it works just fine (over two years now). Also have a Bosch blue coil and I didn't add a ballast resistor, but that's dependent upon the model blue coil you're using. Some have internal resistance, some don't.

[ChrisFoley]

Do you know which cylinder is missing?
its most likely an idle jet

[VaccaRabite]

I don't think its an idle jet. all summer long I have been fighting this. I pull the idles, examine them and don't find a blockage. I clean them anyway before I reinstall.

When it is sitting at an idle I can hear it miss every now and again.

I checked my fuel filter and it was clean.
Before putting the gas tank back in the car during my restoration I cleaned out all the silt at the bottom of the tank. It was spotless on installation. All the fuel lines are new - including the tunnel lines which are the Tangerine SS lines.

I don't know which cylinder is missing, though. I suspect that I am loosing two though, as the car will idle just fine all day on three, the only indication being a 100 rpm drop in idle speed. I suspect it is #2 as one of the culprets, but that is more of a hunch right now and not a proven fact.

I guess what I need to do is get out my timing light and start checking to see which lines are missing at idle. If the miss is electric, the timing light should fail to flash when a miss occurs.

[VaccaRabite]

How do you tell which blue coils have the internal ballast resistor?

Zach

[ME733]

.........AT what R,P.M have you set your idle at?___________. what is the ignition timing at this Idle rpm?_____________.....what is the total ignition timing ? (all in) _____________.

[VaccaRabite]

Idle is set at 1100 RPM. I am using the grey springs for the Mallory which is I think either 12 or 16 advance at idle, but I have never timed for idle. I set timing at 28 degrees full advance, which I hit by 3K rpm.

Zach

[ChrisFoley]

Idle is set at 1100 RPM. I am using the grey springs for the Mallory which is I think either 12 or 16 advance at idle, but I have never timed for idle. I set timing at 28 degrees full advance, which I hit by 3K rpm.

Zach

The mallory distributor springs don't govern degrees of advance, only the shape of the advance curve.
Amount of centrifugal advance is controlled by re-clocking the advance plate, using a plastic gauge provided in their spring kits.
We also bend the spring tabs to raise the rpm where advance begins.
You should have 16 degrees of centrifugal advance, starting at 12 degrees initial. At 1100 rpm idle I wouldn't be surprised if you are already seeing some centrifugal advance.

[VaccaRabite]

The mallory distributor springs don't govern degrees of advance, only the shape of the advance curve.
Amount of centrifugal advance is controlled by re-clocking the advance plate, using a plastic gauge provided in their spring kits.
We also bend the spring tabs to raise the rpm where advance begins.
You should have 16 degrees of centrifugal advance, starting at 12 degrees initial. At 1100 rpm idle I wouldn't be surprised if you are already seeing some centrifugal advance.

I got my Mallory when I got the engine. I had always wondered what the little ring of red plastic "keys" were.

I had to replace the optical sensor last year. Would that install have caused my advance plate to shift? I followed the instructions on the optical reinstall and don't remember needing to reset anything. But that does not mean I was supposed to.

This issue is infuriating. When the car is running, its running like a bat out of hell, very strong. but when it starts missing, driving the car at lower RPMs can become very challenging. Part of the reason that I have my ilde set high was to give me some lead time before the engine would stall out during a missfire event.

Zach

[ChrisFoley]

I had to replace the optical sensor last year. Would that install have caused my advance plate to shift? I followed the instructions on the optical reinstall and don't remember needing to reset anything. But that does not mean I was supposed to.

Replacing the timing unit shouldn't affect advance settings, but you do need the optical unit out in order to set the advance.
You have to loosen the two Torx screws to move the plate, then insert the 16 degree key in the opening, close the opening against the key and re-tighten the screws. Bending the spring tabs to tighten the springs is just as important as setting the max advance.
Once you determine exactly which cylinder is dropping out you'll be able to diagnose the problem.
If you don't have a pyrometer to check which exhaust pipe is cold, you can pull one plug wire at a time from the distributor cap (using insulated pliers). The one that doesn't affect idle is connected to the bad cylinder.

[ME733]

.........thanks chris, EXCELLANT advise.......So Vacca, what you should do is put a ...adjustable strobe timing light on the engine and determine what your ignition timing range is through out the engine rpm range......you probably need MORE timing at Idle and lower rpms.......Here,s why I say this...In a previous post you said that you installed a camshaft with "lots" of exhaust duration., the additional exhaust opening , in consert with the intake cycle,is cooling off the spark plugs too much, causing them to misfire in a "rich" mode.(low RPM,s.)...This is one reason you can use/have found the highest heat range spark plugs to work., they reduced (but did not eliminate) misfiring....eventually, after you sort out the timing issues, You may need to "lean up" the idle circuit/acceleration pump circuit to really get the engine perfect.

[Gint]

How do you tell which blue coils have the internal ballast resistor?

Zach

Get your meter out. If the resistance across the +/- terminals is 3 ohms or more, it's internally ballasted. If it's less than 2 ohms, it's not.

[VaccaRabite]

Is the blue coil the preferred coil for the mallory? Or should I need to buy the mallory coil? Would moving to the mallory coil give me a larger spark?

I am thinking I am going to pull the dizzy ad just make sure it was set right, since I was not the person who set it up i the first place.

Zach

[ME733]

.VACCA.........Check all the ignition timing positions, Before you pull the distributor......that way you will have a base line of where you are at.....and what changes/ direction/where you should go.

[jeffdon]

You know, I am running a carbed 2056 with 494 webcam, Jets are 65 idles, 125 mains, 200 air, F11 e-tubes. I went to a malllory with the grey springs, hoping for a big improvement over the 009. While the car does pull stronger, its still sluggish in the low end, and when i mash on it. WTF? Should I go up on my idles and mains? Thinking maybe i need to get a wide band O2 gauge to diagnose it, but having just popped 300 for the Mallory, I am not quite ready to shell out another bunch of cash.

[VaccaRabite]

You know, I am running a carbed 2056 with 494 webcam, Jets are 65 idles, 125 mains, 200 air, F11 e-tubes. I went to a malllory with the grey springs, hoping for a big improvement over the 009. While the car does pull stronger, its still sluggish in the low end, and when i mash on it. WTF? Should I go up on my idles and mains? Thinking maybe i need to get a wide band O2 gauge to diagnose it, but having just popped 300 for the Mallory, I am not quite ready to shell out another bunch of cash.

my guess is that you are over rich.
my engine is VERY similar to yours. My cam is like a 494 with a little added exhaust duration. My when I went from 60 idles to 65 idles I started getting a LOT of plug fouling and low speed misses unless I kept the engine turning above 3K (ie, get off the idle circuit.)

Zach