• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

Fuel Injection

Share this page

drambuie said:
That is a COP coil...... they connect directly to each spark plug with a stainless steel spring, each coil is mounted to the head. They fuction as a coil and spark plug wire all in one! its for better timing, fuel emissions. Look on there web site for more info..... I just did!:smile:
Click to expand...

For those wondering COP stands for "coil on plug". They are used on cars with computerized ignition and fuel injection. A computer fires each coil individually controlling advance and retard as well, no distributor needed.
 
drambuie said:
That is a COP coil...... they connect directly to each spark plug with a stainless steel spring, each coil is mounted to the head. They function as a coil and spark plug wire all in one! its for better timing, fuel emissions. Look on there web site for more info..... I just did!:smile:
Click to expand...
Theoretically can we add six COP to our AH without shift to ECM control unit and ignition system?
In this case Distributor can give only BT (12 volt) input to COP ?
 
Andrea, you would have to modify the distributor into a 6 way switch, since 12V would not jump the gap between the rotor and cap. Or, you could fire all 6 COPs at the same time, every time, but I suspect the points would not last very long supplying current to 6 coils concurrently.
 
Theoretically, yes. However, the advantage/necessity of COP ignitions is that the ECM can fire any plug it wants to, whenever it wants to, giving much more precise control of timing for a greater range of driving conditions (hence better performance, use of different grades of gas, etc.). Also, you don't have to run high tension lines to each plug.

I haven't heard anything lately, but problems were rampant with earlier ECM/COP designs. Some VWs, in particular, had a lot of problems with the COPs. The Lincoln LS was notorious for COP problems. My parents have one, and were about ready to junk the car--they otherwise loved it--until I found a website where a pro mechanic had diagnosed the problem: failing COPs could cause a voltage spike on the primary line which caused the ECM to shut down. My dad--who's 82 but still likes to romp on it when he has an excuse--got shook up when his engine quit while trying to merge on a fast and busy freeway (I5 in California). Changing the occasional bad COP would help in the short term, but the problem wasn't solved until we replaced all 8 COPs with a newer, presumably better, design sourced from NAPA. Note the COP is a small, plastic-encased design that is doing basically the same job as an older, metal-encased and oil-filled coil (I think COPs use a little different circuitry, with some aspects of a capacitive discharge design, but I'm not sure about it).
 
Tanks for replies
I continuing my theoretically inquiry:in my opinion EFI, ECM, and Fuel injection system are hard matter for the integration in one oldest cars as AH
only few guys as Steve and Phil have the capacity to solve all the involved problems.
I will find one more simple (and less expensive) solution, and also less invasive for my AH aspect-- and at my capacity limit.
Looking at Phil good solution to hide the six COP.
I have one brainwave, connect my 123 Distributor-point less, One modern electronic evolution, more efficient, of the old distributor-
that have one good curve timing control and a connection to the intake manifold that modify the advance on the base of open throttle position
and connect it to six COP- this probably avoid the problems advanced by Chris - and partially the ECM lack, prospected by Bob .....???!!!
https://picasaweb.google.com/lh/photo/RvSLhahLAsVdg3VBEh4GgtMTjNZETYmyPJy0liipFm0?feat=directlink
 
Current to COPs is primary--i.e. 12V--electronically switched to each plug by the ECM. The distributor 'switches' high voltage--15,000V and higher--hence the robust contacts. The air gap between the rotor and cap terminals is inconsequential at 15,000 volts and higher; I don't think 12V would switch very well (if at all) through a distributor cap. Plus, you'd need to run small wires to the COPs, not very practical and would look plain silly. If you want to run COPs you need to switch them electronically; i.e. through an ECM. Firing COPs through an ECM is extremely precise, sending high voltage through a distributor cap is less so (depends on when the spark decides to jump the gap).

All the COPs I've seen have 2 wires going to them; I presume one is a ground lead since the coil itself is isolated (same reason your coil works by grounding through points).
 
Now I've had a brainwave. It would be possible for someone to design and construct a 'smart' distributor cap, with, say, a rotor with a magnet in it. Each of the six (or 4) terminals would have a Hall Effect switch in it that would switch 12V to a pair of wires for each COP. This is similar to how the Pertronix Ignitor works, and is entirely feasible. Basically, each terminal in the cap would be an Ignitor, switching 12V to a COP. The cap would only need a 12V and ground lead (just like Ignitors do). Of course, the cap would probably cost as much as 6 Ignitors!

To be solved would be how to advance/retard the timing with no points.
 
Bob_Spidell said:
To be solved would be how to advance/retard the timing with no points.
Click to expand...

Actually you have answered your own question pretty much since the rotor advances in sync with the points cam so too would the timing if the rotor was triggering the ignition as opposed to 'distributing' the spark.

Modern COPs have the ignitor module built into them so you could just have six hall effect or optical switches in the cap and send a 5V signal to the coils.

Why...? bit of bling maybe? no real advantage on an old plodder over conventional setup.

Andy.
 
57_BN4 said:
Actually you have answered your own question pretty much since the rotor advances in sync with the points cam so too would the timing if the rotor was triggering the ignition as opposed to 'distributing' the spark.

Andy.
Click to expand...

Last I checked distributors advance timing by moving the points baseplate, either via weights or a vacuum mechanism, moving the position of the points relative to the cam. You'd have to maybe attach another magnet to the baseplate to inform the 'smart cap' to advance timing.
 
The flyweights advance the [points] cam so yes you'd lose vac advance.
 
Good point. A performance distributor--not using vacuum advance--would work fine, or you could add another magnet to the baseplate and a pickup in the cap to detect vacuum advance. This is feasible, but I don't know if it's worth the trouble, except you could add other inputs--a MAP or throttle position sensor for instance--and have, in effect, an ECM mounted on your distributor.
 
Also, the COPs don't have to look like they (usually) do. The long 'neck' is only necessary to reach plugs that are buried deep in the head, usually in OHC engines. You could make a 'rail' of 6 (or 4) small COPs that would fit all the plugs on a Healey, and be supported by brackets that bolted to, say, the tappet covers.
 
 
Last edited:
How about that! Someone took my idea and built a product overnight! But, they screwed-up and read 'Honda' instead of 'Healey.'

Theoretically--there's that word again--this could be adapted to a Healey engine. You'd want COPs without the long 'neck,' though (maybe they're necessary to somehow isolate the coil from the plug, but I think it's just because the plugs are buried so deep in modern OHC engines).
 
Yes Bob for our AH the better solution is hide the compact COP under the RX wing
as MCS Phil photos, and connect the sparks with good HT wires and pipes as actually applied at our old distributor, we loss a fraction of the spark power,
but long neck COPs are very invasive to see in our engine bay
 
Phil,
congrats on getting her together and running! Good feeling isn't it? I will be eager to hear of your Dyno results. Best wishes.

cheers,
Lin
 
hi Lin,

Thanks , it will interesting to see what kinda of Hp i make
Phil
 
Phil,
Have you had a chance to get to the dyno yet? I liked the video of it running!... sounds good.
Cheers,
Steve
1963 Austin Healey Works Tribute car w/efi
 
image.jpg Steve,
thanks, will be a few more months, the dyno is last on the list just before the body goes back on . I am driving my neighbours crazy listening to my engine and driving up and down my driveway.

Phil
 
Last edited:
Back
Top