Spark plug boots arcing/frying on headers
Thread Starter
Pro
Joined: Jan 2001
Posts: 602
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From: Aliso Viejo CA
Spark plug boots arcing/frying on headers
Parts:
383 with STRAIGHT Plug AFR190's. Hooker super comp headers. Accel 300 ignition. Plugs gapped at 55.
Problem:
Cylinders 2 and 5 get no spark because they arc from the 90* bend in the boot to the header tube. Also, the boots fry quickly even using high temp wires like Livewires, however I dont know if its the heat or the spark going through the boot that frys them. It causes a pretty light show though. :mad
There is little if any clearance between the boot and the tube, in fact I had to "dimple" or dent the tubes for these two plugs just to get the boots on. Looks like I have to take them off and beat them in further. :cuss
Questions:
1) How much can I dent them in before I start hurting my performance?
2) What if I gap my plugs to like 35? Will this help them not to arc at the headers?
3) I tried accell's "shorty" header plugs. They really are not much shorter than the AC/Delco FR3s and the reach is like .46 as opposed to .75 on the ACs so the spark is inside the plug hole not in the chamber. Any "shorty" plugs that have a .75" reach?
4) Any plugs that are 2 piece, bend, or anything else weird that might help?
5) Other Ideas?
383 with STRAIGHT Plug AFR190's. Hooker super comp headers. Accel 300 ignition. Plugs gapped at 55.
Problem:
Cylinders 2 and 5 get no spark because they arc from the 90* bend in the boot to the header tube. Also, the boots fry quickly even using high temp wires like Livewires, however I dont know if its the heat or the spark going through the boot that frys them. It causes a pretty light show though. :mad
There is little if any clearance between the boot and the tube, in fact I had to "dimple" or dent the tubes for these two plugs just to get the boots on. Looks like I have to take them off and beat them in further. :cuss
Questions:
1) How much can I dent them in before I start hurting my performance?
2) What if I gap my plugs to like 35? Will this help them not to arc at the headers?
3) I tried accell's "shorty" header plugs. They really are not much shorter than the AC/Delco FR3s and the reach is like .46 as opposed to .75 on the ACs so the spark is inside the plug hole not in the chamber. Any "shorty" plugs that have a .75" reach?
4) Any plugs that are 2 piece, bend, or anything else weird that might help?
5) Other Ideas?
Le Mans Master
Joined: Feb 1999
Posts: 5,877
Likes: 1
From: Park Ridge IL
Re: Spark plug boots arcing/frying on headers (Warlock)
From the pics in your sig, it looks like you're routing th wires over the valve covers, would routing them under the headers, and pointing the 90* boot down give you more room?
Also, I've been using the plug boots (made of a fiberglass/cloth material) you slide over the plug wire ends, those really help eliminate burned spark plug wires
Also, I've been using the plug boots (made of a fiberglass/cloth material) you slide over the plug wire ends, those really help eliminate burned spark plug wires
Instructor
Joined: Mar 2002
Posts: 181
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From: Allen TX
Re: Spark plug boots arcing/frying on headers (Warlock)
I had a similar problem with burning up boots on headers. My solution was to start making my own custom wires and custom routing the wires with Made For You looms. I was using Large MSD boots, these boots would end up about 1/8" from the header tube and fry in no time. To gain a bit more distance I switched to a Taylor boot, that isn't nearly as beefy but gives more clearance. With the Taylor boot I can now fit a finger between the primary and the boot. This fix has lasted about 6 months and still going strong.
John
[Modified by John W, 9:58 PM 4/16/2002]
John
[Modified by John W, 9:58 PM 4/16/2002]
Thread Starter
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Joined: Jan 2001
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From: Aliso Viejo CA
Re: Spark plug boots arcing/frying on headers (John W)
Monty:
I am actually pointing them sideways away from the pipe. No matter which direction I point them, the are still like a millimeter from actually touching the header.
I tried the high heat sleeves too, but since the sleeves then touch the header and the boots touch the sleeve, the boot still ends up melting/arcing.
John:
I looked at the taylors, and while the part that goes over the plug is significantly narrower, it looked like the way they are shaped that the actual corner of the 90* would be in about the same position.
I'll try to take a better picture tonight to give you a better idea of my clearance problems.
[Modified by Warlock, 4:25 PM 4/16/2002]
I am actually pointing them sideways away from the pipe. No matter which direction I point them, the are still like a millimeter from actually touching the header.
I tried the high heat sleeves too, but since the sleeves then touch the header and the boots touch the sleeve, the boot still ends up melting/arcing.
John:
I looked at the taylors, and while the part that goes over the plug is significantly narrower, it looked like the way they are shaped that the actual corner of the 90* would be in about the same position.
I'll try to take a better picture tonight to give you a better idea of my clearance problems.
[Modified by Warlock, 4:25 PM 4/16/2002]
Pro
Joined: Jun 2000
Posts: 698
Likes: 1
From: Park Ridge IL
Re: Spark plug boots arcing/frying on headers (Warlock)
You should get L98 style haeds with the angled spark plugs holes.
Even than they are very close, but boots are doing great job protecting the wires.
Ziggy
Even than they are very close, but boots are doing great job protecting the wires.
Ziggy
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
Re: Spark plug boots arcing/frying on headers (Warlock)
I had the same problem with tubes 1 and 3 on my big block. A spark plug boot would last about a week sometimes less. I bought 2 Jacob ceramic boots and wires. They were $40CDN each but end of problem. These ceramic boots are good to 2000 degrees and guaranteed for life. I have run them for 2 years without a problem. One the other 6 cylinders I run accell's 300s.
Thread Starter
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From: Aliso Viejo CA
Re: Spark plug boots arcing/frying on headers (norvalwilhelm)
OK, here is a picture of both plug locations. I thought about the Jacobs boots, but they looked too big to fit. As for swapping heads to l98 style...yeah, thats a cheap idea... :cry
Pro
Joined: Jun 2000
Posts: 698
Likes: 1
From: Park Ridge IL
Re: Spark plug boots arcing/frying on headers (Warlock)
OMG, that is close!!!
I am sorry I brouth that (L98 style) up, but that would be the right way to do it.
You have another choice, but it's not much less expensive: custom headers.
Ziggy
I am sorry I brouth that (L98 style) up, but that would be the right way to do it.
You have another choice, but it's not much less expensive: custom headers.
Ziggy
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Thread Starter
Pro
Joined: Jan 2001
Posts: 602
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From: Aliso Viejo CA
Re: Spark plug boots arcing/frying on headers (88WHITE VETTE)
I know. The whole thing was a clusterfu--. But they are brand new AFR190s with maybe 100 miles on them. Yes, I should have gotten the L98 angle ones...wish I had. Just looking for a cheaper/easier way than new heads.
Thread Starter
Pro
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From: Aliso Viejo CA
Re: Spark plug boots arcing/frying on headers (Warlock)
BTW, the pics above are 2 different locations. The one that has 8 on the wire is really #5 the other is #2.
What about a thicker header gasket, or doubling/trippling it? How much of a sealing problem would ther be? Wouldn't give me lots of room, but would give me more...
What about a thicker header gasket, or doubling/trippling it? How much of a sealing problem would ther be? Wouldn't give me lots of room, but would give me more...
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Re: Spark plug boots arcing/frying on headers (Warlock)
Yeah you could do that. You may have a seal problem after a while, but who knows. I would use the copper kind. They will not burn through like the fiber ones as quick if a small leak does occure.
You may also be able to get under the car and bend them out a tad. Mine were hitting the motor mount and rubbing the frame a tad. I got under the car with a pry bar and moved them a good .25 inch. Just do it slowly and steadily. They will most definately move some. Provided there is room on the outer side.
Good luck.
You may also be able to get under the car and bend them out a tad. Mine were hitting the motor mount and rubbing the frame a tad. I got under the car with a pry bar and moved them a good .25 inch. Just do it slowly and steadily. They will most definately move some. Provided there is room on the outer side.
Good luck.
Pro
Joined: Jun 2000
Posts: 698
Likes: 1
From: Park Ridge IL
Re: Spark plug boots arcing/frying on headers (Warlock)
Probablly not the least expensive solution, but maybe: take those headers off the car and take them to your local "header shop" mark where they need to be altered and tell them to make some extra room for the spark plug wires boots???!!?
Just idea :confused:
Just idea :confused:
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
Re: Spark plug boots arcing/frying on headers (Warlock)
My big block called for Accel 276 plugs. In the problem cylinders I ran Accel 276s. The ceramic part is about 3/8 of an inch shorter then normal plugs but the internal part is the same. The Jacob ceramic boots will stand the temperature and I found them to be small enough to fit. They come in a 90 degree bend. Worked for me.
Instructor
Joined: Sep 2001
Posts: 155
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From: Helena AL.
Re: Spark plug boots arcing/frying on headers (norvalwilhelm)
Norval is right, the Jacobs ceramic boots are not as big as you might think. I could not get a normal boot to stay on my car, it would arc through in a matter of days. The boots would crumble in my hand when i took them off. The Jacobs wires fixed that problem and i am also using heat sleaves over the boots which helps cover the wire close to the headers.
Racer
Joined: Aug 2001
Posts: 457
Likes: 0
Re: Spark plug boots arcing/frying on headers (Monty)
MONTY,
When you get that 1200 h.p. to the street, i definetly want to make the trip down from Mundelein, to see it. Let us know when it is completed.
I have Super Comp HEaders on my BB and use Fiberglass boot covers . Look in Jegs catalogue. They have lasted over 3 years now and 2 of them are touching the headers ; no burning of the covers OR the plug boot . I even painted the boot covers with manifold black paint so they look better, and the paint sticks well to them.
Dave
When you get that 1200 h.p. to the street, i definetly want to make the trip down from Mundelein, to see it. Let us know when it is completed.
I have Super Comp HEaders on my BB and use Fiberglass boot covers . Look in Jegs catalogue. They have lasted over 3 years now and 2 of them are touching the headers ; no burning of the covers OR the plug boot . I even painted the boot covers with manifold black paint so they look better, and the paint sticks well to them.
Dave
Drifting
Joined: Sep 2000
Posts: 1,355
Likes: 0
From: Germantown Maryland
Re: Spark plug boots arcing/frying on headers (Warlock)
Two things to try... Taylor makes a 45deg boot that might work better, did for me. Also you can wrap that portion of the header with heat wrap, from pep boys, autozone or any speed shop.
:flag
:flag
Thread Starter
Pro
Joined: Jan 2001
Posts: 602
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From: Aliso Viejo CA
Re: Spark plug boots arcing/frying on headers (drive it)
This weekend I wedged a prybar in there and bent both tubes some more, I now have 1/4" clearance from the boots to the headers and am running on 8 cylinders again, remains to be seen if that will work long term. But yes, even if I have to put brand new wires on right before we do it and I fry them doing it, I will be ready. :smash: