...any truth to it? I've read on some boards that it is necessary to cancel misfires of the plugs. I always thought it was just the opposite. Facts and reasons...

 

Not sure the post'll be Advanced worthy in the long run, but I too would like some feedback on this. I have been getting conflicting opinions on this subject as well.

 

Good question.

I've had wires laying in close proximity on a dyno and not had
any issues.

The trick is to have them cross at 90' angles if they need to touch.
Electro-magnetic fields will be inducted at higher rates if the wires
run parallel.

Here's an additonal related question:

Will drilling a hole in the distributor allow for ionized air to escape
reducing under-cap arcing, or is that a nice path for moisture to
enter?

That's a toss up too...I've read pros and cons about doing that.

 

I'm going a little off topic, but it seems to me that it can't be that hard to plumb a small vacuum hose to the intake to get the benefit without the drawback.

 

That's exactly what I here...
And having wires running parallel to each other especially with HEI systems could (will) cause misfires!...
To get a little more technical, can anyone explain how an induced pulse can actually misfire a sparkplug...

 

Basically what happens is a form of cross talk. One plug wire pulls a bit of the charge from the closest one and inadvertently fires the plug attached. Path of least resistance. You know how ignitions are always sparking off to whatever they can reach if you have a burnt wire or old worn out ones.

This is really a huge concern after your plugs wires become worn and the silicone sheilding weakens. This allows the wire to have less insulation, therefore not holding the charge in the actual wire, letting it excape to whatever it find closest to conduct it, which is the plug wire laying next to it

-Shannon

 

I have a very difficult time understanding how induced energy
will trigger a spark in an adjacent wire, yet will not ground itself
out to the engine block beforehand?

The energy escaping from the wire must be enough such that
it will bridge the gap in the spark plug. We're talkin several
thousand volts to jump a 0.040" gap...yet the wire laying on
the valve cover, or intake will not ground out?

How much energy can actually pass the insulator and shield of
two wires and still have enough voltage to fire the plug?

Inquiring minds need to know...I'm thinking poor shielding, or
excessive secondary voltage may cause a jump in wires.

The EMI energy travels along the wire creating a "field" around
the wire. If another wire sits close enough to that field, the energy
will transfer over (similar to a power transformer winding - primary
to secondary windings).

That's about as technical as I can explain. I'm sure you'll find
thousands of diagrams if you searched the internet.

 

There's a difference between shorting and inducting. With a short, electrons find the the path of least resistance. That is, if the insulator is worn the wire will short to any nearby conductor.

Inducting is a whole other matter. Any current creates a magnetic field. Current and magnetic fields are very closely related. Current through a wire creates magnetic fields, and magnetic fields around a wire create current. Current through the "firing" igntion wire creates a field that induces current in any nearby wires, the magnitude depends on the amount of current, the proximity of nearby wires, and the angle between them. This is how induced currents work, no physical contact needed, in fact it'd work in a vacuum. If it wasn't for this principle our alternators wouldn't function

That said, I was worried about running my wires together underneath the alternator but never had any problems. Given some numbers we could calculate the induced current, I've had enough EE calculations lately that I don't car to however

 

It is a very simple consept.
The plug wire firing is just like a raido transmitter and the plug wire next to it is like an antena (sp?, don't care) and it picks up the transmissioin and repeats it through the spatk plug.
It's an EMF signal every thing makes it that has AC or pulsing DC going through it.
If you take a cord pluged into your dryer or some thing that has a good bit of amprage going through it and take a multi meter and wrap the leads around the power cord several times (while the unit is runing) and touch the ends together you will read voltage (AC).
Or if you voltage check a wire that should be dead that is run close to a wire that has power going through it will read voltage(like all most 0 to as high as what I have seen, 16 volts picked up inductivly on a dead wire in a 440VAC air A/C unit), I see it all the time in the work I do.
Close together plug wires are the same way.
You could cancel it out by distance or wraping a little wire around the plug wire and grounding it through a capactor (or you will enhance the transmitting effect or the wires if you dont use a capactor).
There arnt too many systems that I dont work on, diesel, gas turbines , hydraulics, air systems, eletronics and more.
The only thing I don't do at work is weld.