Arcing
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Instructor
Joined: Jun 2002
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From: San Diego CA
Arcing
Ok, so the question: How much arcing is normal from the plug wires?
I just finished installing new AC Delco wires. I drove about 20 miles to get a good run in, and came back to a nice dark garage to look at the wires. At least half the boots are arcing at the plug (they had grease/lube inside the boots out of the box), and a couple intermittent arcs at the factory wire clips.
Please do not say "get MSD". That is what I just took off (8.5s), and they lasted about 3 years, and less than 15K miles. It looked like a blue laser light show gone crazy under the hood with those things. They arced from everywhere to anything.
FWTW, 1992, LT1, stock ignition system, the plugs are three year old Denso Iridium IT20. I checked a couple, and they looked just like they are supposed to.
Thanks-
I just finished installing new AC Delco wires. I drove about 20 miles to get a good run in, and came back to a nice dark garage to look at the wires. At least half the boots are arcing at the plug (they had grease/lube inside the boots out of the box), and a couple intermittent arcs at the factory wire clips.
Please do not say "get MSD". That is what I just took off (8.5s), and they lasted about 3 years, and less than 15K miles. It looked like a blue laser light show gone crazy under the hood with those things. They arced from everywhere to anything.
FWTW, 1992, LT1, stock ignition system, the plugs are three year old Denso Iridium IT20. I checked a couple, and they looked just like they are supposed to.
Thanks-
Team Owner
Joined: Mar 2001
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From: Cincinnati, Oh USA
With stock ignition, no arcing should be seen! I own two vettes and I don't see any arcing. Plug wires should be routed through the wire looms that should be in good condition and they should be dressed so they don't touch metal. The spark is supposed to occur at the spark plug gap, nowhere else.
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From: Fort Knox, KY
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With stock ignition, no arcing should be seen! I own two vettes and I don't see any arcing. Plug wires should be routed through the wire looms that should be in good condition and they should be dressed so they don't touch metal. The spark is supposed to occur at the spark plug gap, nowhere else.
Don't forget to replace the black, corrugated flex tubing that covers some sections of the stock wires and coil wire.
It's there to prevent them from touching metal (chafing) and insulate them from engine heat. You can buy it at any auto parts store.
I've had good results with the NAPA/Belden Super Blue Premium Ingition Wires in the 7 mm flavor. And of course, Taylor and AC/Delco-Packard wires are good, too.
Last edited by onedef92; Sep 2, 2010 at 07:23 AM.
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Joined: Jun 2006
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From: FL
I'll post something I spotted recently in my 93 FSM, just to add to the confusion.
Read the reference to "corona" in the circled paragraph and see if it is clear to any of you because I find it mystifying to say the least.
I think my response to "arcing" in the area mentioned above would be to ignore it UNLESS there is other evidence of a problem such as noticeable misfire, wires arcing in other locations are obviously a different situation.
Read the reference to "corona" in the circled paragraph and see if it is clear to any of you because I find it mystifying to say the least.I think my response to "arcing" in the area mentioned above would be to ignore it UNLESS there is other evidence of a problem such as noticeable misfire, wires arcing in other locations are obviously a different situation.
Thread Starter
Instructor
Joined: Jun 2002
Posts: 154
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From: San Diego CA
I'll post something I spotted recently in my 93 FSM, just to add to the confusion. Read the reference to "corona" in the circled paragraph and see if it is clear to any of you because I find it mystifying to say the least.
I think my response to "arcing" in the area mentioned above would be to ignore it UNLESS there is other evidence of a problem such as noticeable misfire, wires arcing in other locations are obviously a different situation.
Read the reference to "corona" in the circled paragraph and see if it is clear to any of you because I find it mystifying to say the least.I think my response to "arcing" in the area mentioned above would be to ignore it UNLESS there is other evidence of a problem such as noticeable misfire, wires arcing in other locations are obviously a different situation.
Yes, that sounds like what I am getting, for the most part. It is odd that I do not have it on all plugs though. I do have some wire arcing, but I will try moving them and adding the plastic sheath before I go and jank them.
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The corona effect is normal. I've seen it myself. The arcing at the wire holders and electrical creepycrawlies along the plug wires you're seeing is NOT.
If there's a tiny hole, break, or crack in the wire insulation allowing current to escape and take the shortest path to ground, that wire should be considered defective. I'd take 'em back and get another set.
If there's a tiny hole, break, or crack in the wire insulation allowing current to escape and take the shortest path to ground, that wire should be considered defective. I'd take 'em back and get another set.
