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
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
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 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
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.
Do you know which cylinder is missing?
its most likely an idle jet
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.
How do you tell which blue coils have the internal ballast resistor?
Zach
.........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) _____________.
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
.........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.
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
.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.
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.
go down to 60 idles and try that. I tried 130 mains, and wet back to 125s. Also, are you using a stock spark heat range? Try going one range hotter then stock if you are.
Oh, and start yer own damn thread! I want my ignition fixed!
Zach
Here's some good reading on the blue coil
http://www.ratwell.com/technical/BlueCoil.html
And also here, I think he gets into the advantages of a jacobs or mallory coil.
http://www.shoptalkforums.com/viewtopic.php?t=124069
okay, so the springs you are using are a direct replacement for the mallory gray ones.
I'll start checkig my coil to see whats what.
I thought one of the benefits of the mallory ignition was a hotter spark then stock. Is this not the case?
Zach
Hey, someone check me here.
Using a meter for testing ohm resistance, I had it set to 200.
Other options were 2K, 20K, 200K, and 2M.
If I had the right choice for measuring ohm resistance, I may have found part of my issue.
My coil is showing 3.4ohms resistance across the positive and negative contacts.
The PO of this engine had the coil wired through the resistor block, and assuming that I needed to do the same, I did. This weekend I will rewire my ignition and see what happens.
However, the resistor was only giving 1.1 ohms resistance also, so I may be using my tester improperly or the PO was using the wrong resistor in the first place.
Also, that thread on STF seems to make a pretty good case for the Jacobs coils. Is there a reason why the blue coils are preferred here? It would seem that a higher power coil would be what you want for a hot rodded motor (even it it is mildly hot rodded compared to some folks here) so long as you don't overpower your plugs, wires and cap.
Asking lots of questions, yeah... But learning a lot.
Zach
Dude... ditch the resistor. You don't need it. You measured right. Your coil is already ballasted.
I agree about ditching the resister. That is going to happen this weekend.
But what about addig a more powerful coil? The Jacobs coils seem to be very sturdy and produce much more power the the blue coil. The Jacobs Ultra has specific mention for the Mallory Unilite in its instruction maual, and is rated at 55K volts over the Bosch Blue 18K volts.
Zach
Check to see if your plug wires will be ok with that kind of voltage increase , also you can open up the plug gap some if you install a higher voltage coil , maybe to .040-.045 to use the increased spark. check your rotor and cap for spark burn on them . Good luck , it seems that you're on the road to recovery!!!
Jack / Jaxdream
Just off the wall ? and something that I came across in installling my 6AL a few weeks ago. They talked about NEVER running consecutive firing cylinders wires right next to each other? Scavaging spark from the cylinder that is firing.
I had mine right next to each other when I first installed but have in the last week seperated them. Have not really drove the car enough either way to know if there was an improvement. It had become so much smoother with the addition of the box I was surprised. Had bought the 6AL mostly for over rev protection(think shift light) on my 2056 in AX situations.
Maybe Chris has some input on this ??
Good Luck, Zach
Okay, partial success!!!
We got out of a training class way early today, so I cam home, rewired my ignition, and collected some more data.
First off, OMFG! That rewire changed the cars starting habits like you would not believe! The "pump the gas twice, crank for 20 seconds until it fires while playing with the throttle" was gone. I started my usual routine and the engine caught so fast I turned off the car in surprise! If the engine stalled I could restart it by just reaching in the window and turning the key. I could almost never do that before. I suspect this will be a major change for the best.
But, it still idled crapily and would sputter and die unless I gave it more gas. You can hear the misfires. So I got out my timing light to check spark on the different leads. I held the timing light on each lead for ~ a minute and just watched the flashes while the engine idled.
My idle for tonight's experiment was set ~1000 rpm.
Plug wire 1 was a metronome. It never skipped a beat that I saw.
Plug 2, 3, and 4 all had seemingly random misfire events. When the engine would sputter you could see that it was not getting spark on that cycle. Most of the time they would fire, but sometimes they simply would not.
However, when I added even just a little more gas, the misfires seemed to go away. Its like the timing got noticeably better around 1400-1600 RPM.
The plugs are new - under 1 hour run time on them. The MSD spiral wound wires are ~1.5 years old - but the fact that the spark gets better as the engine starts to advance leas me to believe that the issue may be with the Mallory's initial timing set before it starts its mechanical advance. I did not check where it was timing in at idle. If I can get time again tonight I will run out and check that.
Any ideas?
Zach
Okay, I just tested my timing at idle (1000 rpm) and 4K.
At idle, it is set at 8 degrees BTDC.
At 4K it is set to 28 degrees BTDC.
This would indicate that I am 4 degrees retarded at idle, and may be my issue.
Also, at idle the timing mark seemed to dance around just a little bit. Less then a degree to be sure, never out of sight. At higher RPM, it was very steady.
Zach
Curious... what exactly did you rewire that gave such an initial improvement? Just took the ballast resistor out? Or was there more?
Sounds like you're advance is set to 20 degrees. I've heard the proper is 16 degrees advance, 12 it idle, 28 all the way in?
Yes. I need to reset the static time. I am really hopeful that this will solve all of my sputtering issues, and I can get back to the real test of finding the best jetting for my motor. I am guessing that when I fix my ignition, all my current jetting info is going to need to be re-examined.
Zach
I FINALLY fixed my static time.
I used the 16 degree key to set timing. That was kind of a chore, and I can see how the PO goofed it. Its probably easier with the dizzy out of the car, but I was being stubborn. It seems like you need two keys to do it, or one key and a lock to keep the dizzy in place while you torque down the set screws.
I retimed the car and extra initial advance certainly helped, but at idle I can still hear the car missing.
Cyl 1 is a metronome. It never misses.
Cyl 2 had an occasional miss. 10 missfired over the course of a minute.
Cyl 3 was missing often. Over my 60 second count, it missed enough that I lost count. I would guess that 1 of every 10 beats it missed.
Cyl 4 was missing too. More then Cyl 2 and less then Cyl 3.
I am going to try a valve adjustment maybe Friday... When in doubt, check the basics. But I don't expect to find any surprises there from when I set it in the spring.
If that does not solve the issue, I am going to move to a bigger coil then the blue one.
The good news if that during the 1/2 an hour or so that I was dicking with the car after setting the timing, it did not try and die once. That is an improvement. But I need to get those misfires under control.
Zach
I am running a 2056 w/ delorto carbs and a mallory distributor.
I put a Pertronix II kit in my mallory distributor and am running the Pertonix .6 ohm coil. The car starts and idles better with the .6 ohm coil. I ran it for a while with points and a resistor on the coil but you can notice a big difference without the resistor.
Are you sure your miss isn't coming from a bad cap or rotor?
My mallory is already electronic - no points.
Is there a way to test the cap and rotor? They don't look damaged...
Zach
A Pertronix II will work with a .6 ohm coil, a Unilite won't tolerate that. If you have to run a resistor why upgrade the coil.
If the cap is real bad you can see stray arcing if you look at the distributor with the car running in the dark.
Hi Zach
Been following your thread and waiting to see how things turn out
as I pretty much have the same setup.
Wondering if your misfire is due to the spark plug wires "leaking" somewhere along the way.
Maybe to ground or to another spark plug wire?
Also, could it be the cap (near the spark plug towers) leaking to the tin nearby.
As you know, you have to pound the tin into submission just to get the distributor in to begin with.
After round 1 with the tin, I repainted it a time or two in the area of the distributor and
also put a layer or two of electical tape on the tin right where the distributor cap is very close to the tin.
Are you sure the spark plug wires are completely seated all the way down in the distributor spark towers?
Its such a tight fit to get the wire and the boots all the way down and it would be a short hop for high voltage to find the tin (ground).
Well, good luck, hope you get to the bottom of it.
Curt
Its not the tin. My dizzy is 180 off, so the #1 lead is where the #3 lead should be (right against the tin.) #1 is the cylinder that never misses a beat.
I am going to try a new cap, and then I am going to move to a bigger coil. The car always had a miss at idle, and I have changed wires so that counts out wires. Changed plugs, so that counts out plugs. That leaves the cap and rotor. They LOOK great, but who knows? So I will try them next.
Zach
Any chance you are running rich at idle? There was a long thread on the samba
about how that can make it harder to ignite the mix.
John
You can run it at night in a dark area and see if the the wires or coil are arcing.
Andrew
What was the end result, or are you living with this rough idle?
Microsquirt with crank fired ignition.
Not done yet, but so not living with craptastic idle.
Are you willing to part ways with your Mallory unilite?
Zach, did you ever get this resolved?
get one of these (coil) and some of those.
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