Mallory ignition questions, Partial success! |
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Mallory ignition questions, Partial success! |
VaccaRabite |
Oct 10 2010, 05:59 PM
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#1
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En Garde! Group: Admin Posts: 13,465 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
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 |
VaccaRabite |
Oct 11 2010, 07:02 AM
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#2
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En Garde! Group: Admin Posts: 13,465 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
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. |
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