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: 13,584 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, 10:45 AM
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#2
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En Garde! Group: Admin Posts: 13,584 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
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 |
Oct 11 2010, 11:15 AM
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#3
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I am Tangerine Racing Group: Members Posts: 7,962 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None |
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. |
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