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COP How To w/Drawing

turbo_fox said:
I would think it has to be done in series. considering in parallel the current would probably be near double, I at least wouldn't risk it in parallel
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While this is true, you are also doubling the collapsing voltage by running it in series just due to how inductors work.

I've now got a full COP harness (Or maybe 2... ;)) off a bastard year taurus (2000) that I snagged at the junkyard yesterday. The harness is now cut apart and sitting on my work bench... :D

The difference between the Contour setup and the Taurus setup is that the Contour fires off one "pair" from one pin out of the PCM. The Taurus runs a common 12V and then 6 individual signal wires (one for each coil).

In a nutshell what we need is to find out is the inductance of the COP's as well as to figure out how the coil pack is wired internally. We can then figure out how things need to be wired in order to ensure reliable output without burning up PCM's or having poor spark output... :)
 
turbo_fox said:
I would think it has to be done in series. considering in parallel the current would probably be near double, I at least wouldn't risk it in parallel
Click to expand...

Yeah I agree, if I were going to do it on a test basis I'd either put them in series or I'd do a little test and some math before running them in parallel.

There is a way you can calculate this though. I'm no EE but I remember basic physics classes. IIRC You take both the stock coil and the COP and determine the inductance of each. This is done by putting an AC current of fixed frequency through the coil and measuring the voltages and/or current flow through the coil. You know the resistance at 0 Hz just by measuring it with an ohm meter. You can measure the voltage drop across it by putting a 12Vdc current through it. Then you measure the voltage drop when there is an AC current through it. Adding a resistor to the coil will help keep the voltage values low and can help when computing the math of an RLC circuit.
Anyway, end result you get Inductance.
Then you compute it for the COP coils individually and from that point you can compute various values so that you can make the circuit have the correct impedance for the factory PCM, or you can start with values that maximize the spark output of the COPs.
Then you wire them in either series or parallel, whichever yields the closest characteristics of spark output and behaves like stock.
To change the circuit impedance you can add resistors, capacitors, or even add another coil. You might want to filter each input circuit for the coil pairs anyway for clean spark and less EM interference in the radios.

That's my fifty cents worth on doing it right.
 
I have a harness made up and ready to test. I need to get my SVT out of storage so I can test it out. If I get ambitious I may be able to test it Saturday after I replace the e-brake cables... :)

I picked up one of the Mustang MAF harnesses so my harness will be a direct plug in too. So, if it doesn't work I can just swap right back... :)
 
wasnt that a great idea? i figured thats what the "pro made" harnesses would have, instead of splicing, but apparently im wrong.

anyway, is there an updated drawing with the filter cap in it?
 
In a nutshell where the 12V splits between coils 1, 2 and 3 you solder in the connection there. The harness I made up (and tested on my 2.5 last weekend) had the cap connector spliced in there. I made my test harness using the mustang MAF connector and plugged everything in.

No issues at all with misfires, started and ran like a champ. High load, low RPM seemed fine and it pulled exactly the same as with the coil pack/wires.

EDIT: Try to make the wire lengths for the 12V feeds the same length. It theoretically makes no difference but this is how the taurus is wired and how I set mine up... ;)
 
Another happy camper reporting succesful conversion of coil pack to Coil On Plug using that wiring diagram (with the addition of the capacitor). Works flawlessly. :cool:
 
flyguyeddy said:
wasnt that a great idea? i figured thats what the "pro made" harnesses would have, instead of splicing, but apparently im wrong.

anyway, is there an updated drawing with the filter cap in it?
Click to expand...

yeah, and I bet the instruction set only has the words "it's self explanatory"

after the following failure of your engine, you will be called a n00b, and asked to fork over $3500 for him to do your 3.0 swap...

and of course, you will be told the failure of your build had nothing to do with the very detailed instructions of "it's self explanatory" :laugh:
 
I know it's been said in here, but this is sort of an epic thread, whats the deal with the cap? I know nology makes plug wires with a cap to act as a band-aid on a weak coil just like how a cap works for a crap battery in a stereo, but I'm unsure of exactly where it would go here with the cop. I have a complete 04 harness and would like to start working the kinks of this out, especially since my 02 coil pack may be suspect and I'd like to sort out any future problems while I can.
 
Guys I'm really sorry I haven't gotten back with a better drawing...I just haven't had the time. I am really glad to see that a number of folks are doing this and not paying for it. Regarding the capacitor:

1. It's there to ground out transient signals/voltage spikes. Why? they may interfere with the timing, quality and power of your spark. They may also damage upstream electronics. How? A capacitor does not allow DC such as the your 12V system voltage to flow through it, so connecting a wire from your hot 12V power in to ground through the capacitor does not ground out your system. However, a broad range of AC frequencies (referred to as "noise") will ground out through the capacitor, hence "cleaning" up the voltage. The capacitor that Ford chose for this application probably is focused on common frequencies found under the hood of the car.

2. Where does it go? The best place to see this is on your stock ignition: It runs from the 12V power wire (going to your coil) and is attached and grounded to one corner of your coil. With COP you can just re-connect the capacitor to a handy valve cover bolt at the back passenger side. If you do this right you don't even have to change it's connection from stock as it's already connected to the 12V wire ( which is why I did not include it in the original drawing). If you end up doing more drastic wire work, just make sure that you connect the capacitor's wire near where the 12V splits to the various COP plugs.

I know pics are better, but honestly if you can't figure it out with this much info you might consider getting someone to help who's comfortable doing this kind of stuff.

As an update, mine is still running strong with no misfires, codes or trouble.
 
Mosh

I just completed the COP on my 99 SVT with an 05 3L. I have a question reguarding the capacitor. There is one on the SVT harness and there is one on the COP harness. Im keeping the one from the SVT harness but what if I were to leave the other one attatched and bolt it to the rear valve cover? Would it cause interference?
 
Only use ONE....you will end up changing the frequency range that is grounded....parallel capacitance which causes the capacitance to increase to the sum of the two capacitors. This would focus on very different transient frequencies. Why take the chance that this is a problem when ONE does the job. Just cut one off and insulate the end.

From Wiki:

Decoupling
Main article: decoupling capacitor
A decoupling capacitor is a capacitor used to protect one part of a circuit from the effect of another, for instance to suppress noise or transients. Noise caused by other circuit elements is shunted through the capacitor, reducing the effect they have on the rest of the circuit. It is most commonly used between the power supply and ground. An alternative name is bypass capacitor as it is used to bypass the power supply or other high impedance component of a circuit.

For capacitors in parallel

Capacitors in a parallel configuration each have the same applied voltage. Their capacitances add up. Charge is apportioned among them by size. Using the schematic diagram to visualize parallel plates, it is apparent that each capacitor contributes to the total surface area.
2f5b978fd081ea63e204909addf3d028.png
 
svttour said:
All I understood was NO! lol but ok I will cut one off.
Click to expand...

Leave them alone... Read this for more info: (scroll down to using bypass capacitors) http://www.seattlerobotics.org/Encoder/jun97/basics.html

Using two capacitors in parallel as decoupling capacitors (power to ground) will filter two different frequencies instead of one alone. It's true that two capacitors in parallel will add up to equal a larger capacitor and the total capacitance increases but they still act as two separate capacitors for filtering frequencies which is what you are concerned about here. It won't hurt to use two caps it will only help to further reduce noise (if they are different sizes) so leave them alone.
 
Blackcoog said:
Leave them alone... Read this for more info: (scroll down to using bypass capacitors) http://www.seattlerobotics.org/Encoder/jun97/basics.html

Using two capacitors in parallel as decoupling capacitors (power to ground) will filter two different frequencies instead of one alone. It's true that two capacitors in parallel will add up to equal a larger capacitor and the total capacitance increases but they still act as two separate capacitors for filtering frequencies which is what you are concerned about here. It won't hurt to use two caps it will only help to further reduce noise (if they are different sizes) so leave them alone.
Click to expand...


I read this after I already cut it. Oh well it wont hurt anything.
 
Coil Over Plug or Coil On Plug.

It is the single ignition coil above each spark plug that has become common on cars newer than ours. All of the 2001 and newer 3.0 engines that are being used for 3.0 conversions on our cars have COP.
 
No not all of them. It was kind of liek a on off thing for some reason. My first 3L was a 01 i think and i was the wrong one cause it didnt have the wayter pump pully on the cam it was up front but it had COp. I had to ship it back and get a 02 which did not. The 04 taurus motors didnt come with them but the 04 mercury sable motors do. Dont know why ford did it like that
 
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