Copper Coil Pack Mod

Maisonvi

Grass-Roots Vendor
Here is my quick and simple write up on how to do the copper coil pack mod. The point of this is to replace the steel springs that are in your coil pack with something a bit more conductive and robust. If you are BT and experiencing spark blow out, this maybe what you need to help open your plugs back up.

This is how I did it. You can probably do it with less tolerance and tools, but I’m a bit OCD when it comes to this type of thing.

Things you will need:

8mm socket

Approximately 1 foot of 4-gauge solid copper wire (Home Depot, Lowes, Menards should all have this)

A hack saw

A cordless drill motor

Files

Calipers (a fine resolution scale will work too, but I like the accuracy of calipers and you can get some from harbor freight for around $10 that will work fine)

Bench vice
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Step 1: Pull all 4 of your Coils from your car. If you have a TMIC or FMIC piping in the way, that will have to go. Un-plug all 4 connectors and remove the one screw holding down each coil pack. They should then come right out.


Step 2: Straighten out the copper coil as best you can (the straighter the better. You will see how well you did in step 4). Clamp the copper in the vice leaving yourself room to mark and cut it. Take your scale or calipers and make a mark at 2 and 5/8” on the copper rod.

Step 3: Carefully with the hacksaw, cut just to the long side of the mark you made. Cut too close and the rod will be too short. Cut it too long and you will have to spend more time later taking it down. I went just to the other side of my Sharpie line
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Step 4: Put the cut piece in the drill chuck. This is where you will see how straight you made the copper. If it’s spinning all over the place you didn’t get it very straight. It doesn’t have to be perfect, but I tried to get mine spinning as round as possible.
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Step 5: Clamp your file pointing vertically in the vice. You don’t have to crank on it super hard, shouldn’t really go anywhere.
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Step 6: Using the drill, chamfer the edges and put the flat end up against the file as it spins to “machine” down the ends. Once you have gotten both ends cleaned up and flat check the length. Repeat until you get the correct length. If you so feel inclined I cleaned mine up with a bit of sand paper and scotchbrite when I was done.
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Step 7: Disassemble the coil. The bottom half should just pull apart from the upper section. Inside you can remove the spring. Press the copper rod into the top half until it makes contact with the internals. I put a bit of conductive grease on the end of it to aid in conductivity as well.
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Step 8: Reassemble the coils, and reinstall them. Should be good to go now with more spark!
 
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I chose to use heavy braided wire, slipped it in-between the original spring. Current travels on the surface, this is why most high current systems use fine wire. In this application Fine wire wouldn't work.
 
I chose to use heavy braided wire, slipped it in-between the original spring. Current travels on the surface, this is why most high current systems use fine wire. In this application Fine wire wouldn't work.

Sorry, are you saying you did that on your mazdaspeed coilpacks or other coilpacks? If on the mazda, do you have pics? The adjustability of a spring would be nice.
 
Sorry, are you saying you did that on your mazdaspeed coilpacks or other coilpacks? If on the mazda, do you have pics? The adjustability of a spring would be nice.

On my speed. I'll pull a coil and snap a pic. All i did was use 10g or 8g can't remember right off hand. I stripped the insulation and ran the wire on the inside of the spring.
 
On my speed. I'll pull a coil and snap a pic. All i did was use 10g or 8g can't remember right off hand. I stripped the insulation and ran the wire on the inside of the spring.

Not a bad idea. The 4 gauge is just nice as it fits, but the wrong length would make it more difficult so I like the wire option
 
Crap, I'll pull a pack as soon as I get home from work. I prefer it over the solid wire set up.
 
Interesting. What's the difference in resistance between the steel spring and the wire?

Seems like a cheap and effective modification to prevent problems in just about any setup.
 
That's basically what i'm doing. I run 8 gauge wire inside the spring, since the current travels on the outside of the wire this should significantly reduce the resistance.
 
can someone show or describe the contacts inside the coilpack. what are the spring and wire touching? if the wire is longer than it should be would that apply more force on the spark plug making better contact? does the length of the wire effect this amount of contact? what do the contacts looks like?
 
The coilpack has a little pocket. you cut the copper wire to meat inside the coilpack and rest slightly above the the plug so when you insert the coilpack you get a solid connection.
 
not the best description lol, so what your trying to say is that the wire itself will touch the plug. there is no clips inside the coil to grab the plug connector? Some spark plug boots snap on when you push them and I know the ms3 coils dont do this so I am wondering whats really inside the tube.

It sounds like your saying there is nothing and the spring itself directly touches the spark plug (or in the case of the mod the wire itself).
 
Correct, the factory spring just rests on the top of the plug. the boot has a little retention spot to help hold the spring. and the coil itself has a small indent to retain the spring as well. A lot of guys remove the spring all together and replace with a solid piece of copper.
 
So I know what the top of the spark plug looks like, but what does the contact inside the coilpack look like? is it s small plate of metal ?
 
ok cool its a cup, thats what I was looking for. I am trying to decide if the solid wire is better than the stranded wires. With the top of the plug being flat and the other end round it might be possible with the thicker solid wire to get a good solid connection if it is shaped to the cup and plug.

why do you like the stranded wire better
 
I really don't think it matters. electrical current travels on the surface of the wire, think of it this way. you battery cable going to the starter is multi-strand, high performance audio uses even finer wire. That's why i went strand. kept the spring as a holder and a guide to the length.
 
with the audio wire they use so many strands because its cheaper. The better cables have less wire with higher gauge. I ran into a problem with the high strand wires they don't flow current for shit and they are all rated above what they can actually handle. I found this out the hard way by installing my battery in the trunk and using 0 gauge stereo wire. The wires would get hot and melt when trying to start my car, but the theoretical current limit should be good for the cable and it is not. The Fuses they sell for these systems will never pop because the wire cannot even handle that much. After several I mean SEVERAL fuse holders, wire segments and other wiring components melted I went with 4/00 Wire that is only 330~ strands of heavy ass copper and I barely got it installed as the bend radius is horrid. I installed that with some special high flow fuses and I have not had to replace a fuse or wire since.

this wire is BEAST, and I have never seen anything like it, but I got fucking tired of almost catching fire and my car not wanting to start. I had to cut out the factory power cable that goes from alternator to ECU because it was fried too, I ran this from trunk battery to alternator then to starter and then i ran very heavy 2/00 wire from starter to ecu/fuse junction.

http://www.delcity.net/store/4:0-Gauge-Battery-Cable/p_804958.h_804965.t_1
http://www.delcity.net/store/MEGA-Fuse-Holders/p_795652

the melting I experiences always occurred at the spot of MOST resistance such as the fuse holder or ring terminals where a connection is being made.

I bought the special 4/00 ring terminals which are thicker than a nickle and I used the special anvil/guillotine style hammer tool to hammer on the connectors. This wire will outlast the car and I get rid of the car I should almost rip it out and recover it.

To add to my point above about cheap audio wire, they are not even made of copper most the time, they are aluminum or tinned copper or some other cheap replacement for pure copper. Even when they say its copper when yous trip it, its not
 
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20160806_183654.jpg 20160806_183711.jpg Wow realized i never added pics of the wire. Super fine stereo wire is for sound and high current, have you ever seen the inside of a welding lead. Most car stereo shops sell cheap crap. There is nothing wrong with fine wire cables as long as your connections are built correctly. cheap gold plated terminals or other big box store crap wont cut it. I always solder and crimp my leads.
 
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