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HounDawg
04-01-2005, 02:32 PM
Just wondering if anyone has tried to install this technology on their IT car. Coil on Plug ignition is a newer technology where each spark plug has its own ignition coil directly on top of the plug. Because there are no high voltage leads going along the engine you can get higher voltages and sparks. One problem I've read about is that the coils can short out. Here's what the coil on plug coil looks like on a 6.0L Lambroghini Diablo (that's my parts car I have up on blocks behind the garage http://ITForum.ImprovedTouring.com/wink.gif
http://www.lamboweb.com/images/Repairs%20Page/Plug%20Coil.jpg
There is some more info on COP ignition here (http://hostingprod.com/@aa1car.com/library/copign.htm)


[This message has been edited by HounDawg (edited April 01, 2005).]

dave parker
04-01-2005, 02:34 PM
Dawg
Does not sound IT legal to me.......unless the car came with it.
But i am not a rules nerd.
Kirk? Kirk? Care to wade in here?
cheers
dave
wdcr ITC#97

HounDawg
04-01-2005, 02:42 PM
ITCS 17.1.4.D.1.e. "Any ignition system which utilizes the original distributor for spark timing and distribution is permitted. Internal distributor components and distributor cap may be substituted. Crankfire ignition systems are prohibited unless fitted as original equipment. Any spark plugs and ignition wires may be used. Ignition timing is unrestricted."

JohnRW
04-01-2005, 03:02 PM
It would be pretty easy to construct a protest on the grounds that a system using the unitized 'coil - plug boot' was a vestigial part of a crank-fire system.

After all, if you're not generating HT until it gets to the coil, just what is it that your "original distributor" is actually doing, other than just spinning around ?

Bryan Watts
04-01-2005, 03:58 PM
That's the stock setup on ITS BMW's.

joeg
04-01-2005, 05:49 PM
I say the rule allows it!("any ignition system" means... any coil and any number of coils)

However, you probably would never enjoy the full value of such devices without a crank trigger--which of course would be illegal unless OEM. An OEM distributor introduces far too many inaccuracies into such a sophistiocated set-up.

My McClaren parts car is up on blocks...

Cheers.

BMW RACER
04-01-2005, 06:56 PM
My question is: Do you have to have them installed by The Blue Man Group?

SilverHorseRacing
04-01-2005, 07:59 PM
My 93 Mustang uses 2 coil packs, 2 plugs per cylinder... crank trigger was OEM there. Since the trigger is OEM, if I was bored (which I'm not) I could probably rig up the latest COP setup onto it and be legal, according to the rules.

Again though, I'm not that bored, too many parts to break, and my system works just fine as it sits.

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-Marcello Canitano
www.SilverHorseRacing.com (http://www.SilverHorseRacing.com)

HounDawg
04-01-2005, 11:16 PM
Originally posted by Bryan Watts:
That's the stock setup on ITS BMW's.

Ahhh...my lack of knowledge of BMW's comes to the fore. Thanks for the info. Not that I'm considering it. I was just wondering.

Greg Amy
04-01-2005, 11:37 PM
Not legal unless OEM.

First, you don't need a "crank trigger". A crank trigger is nothing more than a crankshaft position indicator, and you've got that with a good ole standard distributor! Many a distributor has a light or Hall Effect sensor in it, and that would be sufficient to reference for any high-falutin' ignition system.

However, placing the coil directly on top of the plug would violate the following part of the rule (emphasis added): "...utilizes the original distributor for spark timing and distribution..." Modifying your distributor to reference an aftermarket ignition system is perfectly fine, but if you placed the coils on top of the plugs you would no longer be using a distributor as, well, "a distributor" of the spark.

Any ignition system that currently uses a distributor to distribute the spark to the spark plugs must continue to do so. Thus, not legal, Sparky... GA

C. Ludwig
04-02-2005, 06:13 AM
So to clarify. Not legal for any car using a distributor but perfectly legal for any car that using a fully electronic ignition activated by a cam or crank sensor. Miata and 2nd gen RX-7s come to mind.

FWIW, I've used aftermarket COP systems and other than looking cool they offer little benefit in the way of real world performance gains over a good strong conventional system.

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Chris Ludwig
08 ITS RX7 CenDiv

chuck baader
04-02-2005, 08:39 AM
Greg, I respectively disagree. The Distribution of the spark is handled by the wires, which are open as is the coil. Number of coils is irrevelent because you would still use the cap/rotor for spark distribution and timing. I think individual coil packs would be fine, the trick would be to get the ECU to tell the coil pack to fire with the OEM wiring harness. Chuck

Bill Miller
04-02-2005, 09:26 AM
Greg,

That's pretty much the way I was looking at it. Using the COP system w/ a distributor means that the you are now sending a low voltage (12v) 'trigger' signal, not the high voltage 'spark'. So that's where you're wrong Chuck, you would not be using it to distribute the high voltage 'spark', but a low voltage 'trigger'.

Not to mention that you're logic is flawed. Either the wires handle distribution (which they don't), or the the distributor does (which it doesn't, in a COP setup).

While 'spark', per se, isn't defined in the GCR Glossary, "Spark Plug" and "Distributor Cap" are. Both talk about 'high voltage'. Trying to justify using a COP setup, in a car that came w/ a conventional coil/distributor setup, isn't going to fly, and will be considered strained and tortured, at best.

No "I'm a rules nerd" T-shirt for Chuck. http://ITForum.ImprovedTouring.com/biggrin.gif

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MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608

Knestis
04-02-2005, 10:21 AM
It isn't that the part in the picture is strictly illegal: It's the process used in conjunction with it that is the problem, assuming that we are talking about a car that used a distributor in stock form.

K

ITANorm
04-02-2005, 06:22 PM
You guys have failed to consider one important item. 12V ain't gonn'a jump the gap between the distributor cap and the rotor. Modifying it to somehow trigger a low voltage pulse is NOT using the "stock distributor" (IMHO) in the sense the rules intended.

Greg Amy
04-03-2005, 12:30 AM
Chuck, I see what you're saying, but disagree. The way I read the rules, the "spark distribution" is the high voltage stuff. If the high-V stuff was originally going from a coil to distributor cap to rotor to cap to wires to plugs, it's gotta stay that way; that's the "distribution of spark" part. Putting coils on top of plugs removes the distributor, cap, and rotor out of the high voltage loop and flies in the face of the rules both technically and spiritually.

Think of it this way: if the high-V stuff doesn't have to go through the cap/rotor anymore, then we could wire up the tailights through the cap and call it "voltage distribution"...<grin> I don't think that's the intent of the rules.

Of course, the way "rules interpretations" have been going lately, no doubt someone's gonna scream "how in the hell do you know that **NOT** that they intended???" and we'll all be running mega-Streisand ignition systems soon...

ITANorm, since distributor caps are free, it's pretty easy to rig up a gapless brush system to time and distribute low-voltage and -amperage current. However, even easier, if we could avoid running the high-voltage current through the distributor we'd just use the distributor internals as a crankshaft-position sensor to signal a solid-state aftermarket coil-on-plug system...