Your opinion on equal length spark plug wires?

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Tested on a dyno, my Cummins picked up 27hp with equal length plug wires!! Now everyone get some, you read it on the internet ;)
 
Low resistance wires! Who had them? Advertised at a silly low ohm rate.
 
moparlover said:
it's not fully light speed . about 80%

electrons travel in the wire at a quite slow speed opposite the direction of the current. the speed of electricity however is very fast it's actually the speed of the propagation of the electric field
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Exactly, but for the sake of this conversation I didn't want to muddle it up to much. :D


mvh said:
The value of the "speed of light" that everyone is kicking around is for the speed of light in a vacuum -- that is not the same thing as the speed of an electron in a metal wire. But the point is the same -- it's way too fast to worry about the differential lengths of spark plug wires.
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That's right but again, for the sake of this conversation I didn't bother mentioning those details.
I doubt there is an ignition system capable of that kind of accuracy anyway.
 
BigBlockMopar said:
It's about resistance, not traveled distance.

It takes time to send electrons through a wire and build enough current to jump a spark at the plug. It takes (a fraction) more time to build more current to push electrons through a wire with resistance.
.
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Partially correct, wrong terminology. INDUCTANCE is what delays "time."

Resistance has no effect on time, only current
 
moparlover said:
it's not fully light speed . about 80%
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Depends on the wire and dielectric. Stuff like "some RF coax" is around 66% This is called "velocity factor."

http://en.wikipedia.org/wiki/Coaxial_cable

http://en.wikipedia.org/wiki/Velocity_factor

In terms of RF "open wire" (ladder line) up around 90 or better

Common "twin lead" (you guys DO remember "twin lead?" down around 80%

"Stuff like" you would see on CB radio is probably in the 66% range.

I don't know what the lowest is, down to 40%


I think the "real" answer here lies in the loss through the insulation. The longer the wire, the more loss you will have right through the insulation. Some special types of wire like the spiral wound stuff, may have enough inductance to effect loss. This would probably be such that the ignition pulse would be rounded off, maybe not fire so "hard" so to speak.
 
It has very little to do with the speed of light. What is more important is is the discharge circuit inductance and resistance. The inductance and resistance have an associated time constant, it has an effect on the spark duration. But after saying that, the secondary inductance and resistance of an ignition coil is fairly large, and the cable adds a lesser part to that. The inductance is mainly dictated by the coil, the wire inductance is small in comparison. Cable resistance of carbon suppression wires can contribute a significant portion of resistance. A certain amount of resistance is good, it helps reduce EMI, and increases spark duration. Increased resistance also reduces spark current. Any good design has a balance of values, for the specific needs of the circuit.

Coil on plug reduces plug wire length to zip, that is a good thing too. If we keep messing and improving our cars, they will no longer be classic cars.

Here is an article on spark discharge circuits. [ame]http://iupac.org/publications/analytical_compendium/Cha10sec313.pdf[/ame]
 
You would have better luck with equal length nutsack hairs. Part them in the middle and the chicks will like it.
 
This is the first time I've ever heard anything about this. Ridiculous, I think it's not even worth thinking about.
 
Doosterfy said:
This is the first time I've ever heard anything about this. Ridiculous, I think it's not even worth thinking about.
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some people have a lot more time than I do . your cranks probably not indexed close enough to worry about equal length wires, not even millions of a second differance.
 
In my opinion there is never a dumb question, but he may thing so now...........

He hasn't post up sense the first post. Just Saying.
 
No need for him to be bashful. I don't think anybody meant anything personal towards him. I agree, there's no such thing as a stupid question. I think everyone's responses here were to show him just how insignificant a difference he's talking about, not that his question was stupid.
 
69Mope asked a very intelligent question by asking our opinion. He got that from many sources. The hard part is to separate all the chaff from the wheat, if he wants the facts.
 
I saw a prototype ignition system in a speed shop back in the 80's. The guy took a gm HEI distributor housing and mounted 8 (yes eight!) sets of points around the outside (yes outside) of the housing. The primary wires went to 8 coils mounted on the valve covers. One coil and one short wire for each cylinder. He was trying to increase coil "soak time". Think about how many times a single coil has to fire in a motor winding 8 grand. I discussed this system with him then showed him my bike out in his parking lot. Unlike Harleys and most other makes, my Triumph Trident had 3 cylinders, 3 sets of points, and three coils.
 
I just run an adjustable regulator on each of my plug wires to make them all work exactly the same.
 
65cuda360 said:
I saw a prototype ignition system in a speed shop back in the 80's. The guy took a gm HEI distributor housing and mounted 8 (yes eight!) sets of points around the outside (yes outside) of the housing. The primary wires went to 8 coils mounted on the valve covers. One coil and one short wire for each cylinder. He was trying to increase coil "soak time". Think about how many times a single coil has to fire in a motor winding 8 grand. I discussed this system with him then showed him my bike out in his parking lot. Unlike Harleys and most other makes, my Triumph Trident had 3 cylinders, 3 sets of points, and three coils.
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Not new, in fact one of the first ignition design types. Model T's used this with coils in wooden boxes. What we think of as the "normal" points system was developed by a GM Engineer named Charles Kettering.
 
ntsqd said:
Not new, in fact one of the first ignition design types. Model T's used this with coils in wooden boxes. What we think of as the "normal" points system was developed by a GM Engineer named Charles Kettering.
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Uuhh new? I'm talkin 30 years ago and a 60's bike. And yes, it wasn't new then.
 
I'm back. Looking back, it was a stupid question, but, more than once I have questioned car owners why are your wires so messy? Why don't you cut them back so they are not hanging all over the place and the replies were, the wires are equal length for a reason. I will have to look thru my pictures to see if I can find any shots of what I am talking about.
 
Messy routing of wires was to keep the field from the spark from building up in parallel wires, but I never heard of using the same length wires for any reason before in my 50 or so years of involvement.

Doesn't meant it didn't happen though :)
 
No dyno test, but I went from traditional wires to same length wires, and I went from 14.30 to a 13.44, and picked up 4 mph. I then checked the wires to be sure that there was no dead wires, and re-tried with a new set, same results. This was the cheapest 9 tenths I've ever picked up. I also did this to my Pontiac GP, dropped 7 tenths on this car. Durango is next!!!!! Get to cutt'n folks! :D
 
Did you make those runs back to back on the same day at the same track, with only that one change in between them?
 
ntsqd said:
Did you make those runs back to back on the same day at the same track, with only that one change in between them?
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Oh, of course, of course...... almost a full second by equal length plug wires... same day, of course, of course....:glasses7:
 
But then, I went to real long plug wires, and I had to advance the ignition timing 7 degrees to compensate for the long wires, and to run the same E.T.
 
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