Plug wires for cars

[996turbo]

I was at the auto parts store buying wires for a tune up I was doing on my 93 ford ranger. There was 3-4 different options. The prices ranged from $12-50. I called my Porsche mechanic and asked him why. He said there was a big difference in the shielding of Rfa as the noises in a car could really screw with the electronic ignition. He also stated that the better cables gave you better gas mileage.

So what is everybodies take on this? And how does it add to the controversy?

[mtrycraft]

I was at the auto parts store buying wires for a tune up I was doing on my 93 ford ranger. There was 3-4 different options. The prices ranged from $12-50. I called my Porsche mechanic and asked him why. He said there was a big difference in the shielding of Rfa as the noises in a car could really screw with the electronic ignition. He also stated that the better cables gave you better gas mileage.

So what is everybodies take on this? And how does it add to the controversy?

Well, he did make a testable claim. Wonder what his evidence is :) Testimonials, or real hard evidence that can be duplicated :D The former.

[996turbo]

Well, he did make a testable claim. Wonder what his evidence is :) Testimonials, or real hard evidence that can be duplicated :D The former.

I am guessing there is data out there to prove his point as we started discussing it and he sounded as if it was a widely known fact. I will look into it today on the net.

[skeptic]

While I don't know for sure, it seems to me that even the least expensve ignition wire must make a solid copper connection between the ignition system and the spark plugs. I don't see how better wires can improve gas mileage. Any failure of the plugs to completely burn the gasoline will cause raw fuel to enter the exhaust manifold and eventually the catylitic converter where it could cause the converter to become red hot, create extensive damage, and even start a fire or explosion. The combustion of gasoline is a highly exothermic reaction which means that once the reaction starts, so much heat is evolved that it continues to burn as long as more fuel and oxygen is available in the cylinder. Better ignition systems and gasoline catylists strive for smoothness of burn and the initiation of combustion at precisely the right point of the cylinder stroke for maximum power and fuel economy and minimum knock and ping. This improves performance and lenthens engine life. I find it hard to believe that any modern ignition system would not be well enough shielded to prevent interference from RF noise of its own plug wires.

What better plug wires offer is greater resistance to mechanical abuse and high temperatures in the engine compartment. They are usually thick, jacketed in heavy duty thermoplastic, have large boots over the connectors, and high quality connectors at both ends. They may offer improved shielding of rf noise for your car radio. Any decent mechanic will inspect ignition wires during periodic maintenance such as oil changes and recommend replacement at the first sign of deterioration.

I will be interested to see what the experts have to say about this. BTW, a high quality set for an 8 cylinder engine can cost $100 or more.

[markw]

If I remember correctly from my earlier car days, I think that certain wires were composed of a carbon/graphite substance which reduced RFI.

[jneutron]

I was at the auto parts store buying wires for a tune up I was doing on my 93 ford ranger. There was 3-4 different options. The prices ranged from $12-50. I called my Porsche mechanic and asked him why. He said there was a big difference in the shielding of Rfa as the noises in a car could really screw with the electronic ignition. He also stated that the better cables gave you better gas mileage.

So what is everybodies take on this? And how does it add to the controversy?

Resistive wires will reduce the rate of rise of the current pulse that occurs when the spark happens. That will reduce the higher frequency component of the RFI.

Resistive wires will cause the inductively stored energy of the coil to be released at a slower rate, allowing the spark to maintain longer.

If you assume a 30 mil gap at the plug, a very specific voltage is required to initiate the arc. Until the arc occurs, the coil continues to gain energy, the arc removes it.. If you put another 30 mil gap in series, the resultant 60 mil total will require double the voltage to start...That provides 4 time the initial energy, two at each gap, causing a hotter spark. When I started my suzy 550 on cold mornings (4 stroke, 4 cylinder), one cylinder would on occasion, balk...by removing the hood and wire from that cylinder, and forcing a larger gap, the cylinder would work...do that for 30 seconds, the cylinder warms up enough and I replace the hood, drive off..I recall reading about wires that had a built in gap, as well as plugs..but never persued it.

And, sometimes, it's just the quality of the worksmanship and materials...

Cheers, John

[skeptic]

I recall the same. Weren't these called surpressor wires because they reduced rf noise for radios? Neutron's posting is interesting but isn't the type of wire used part of the design of the ignition system for the car and specified by the manufacturer. I wouldn't start experimenting with my own car. They've gotten far more complicated than they used to be.

[jneutron]

I recall the same. Weren't these called surpressor wires because they reduced rf noise for radios? Neutron's posting is interesting but isn't the type of wire used part of the design of the ignition system for the car and specified by the manufacturer. I wouldn't start experimenting with my own car. They've gotten far more complicated than they used to be.

Yes, they were called supressors...and I think the resistive aspect is maintained to this day..maybe someone else can confirm/deny that.

The wire is very specifically designed as an integral part nowadays..substituting a hotter one, or a solid wire one, is probably compromising something else in the system.

Complicated???you are a master of understatement..

Cheers, John

[skeptic]

There was a time not so long ago when tuning a car meant gapping new plugs and installing them in place of the old, replacing the rotor and points in the distributor, adjusting the dwell angle by adjusting the point on the distributor cam where the points opened, checking and adjusting the timing if necessary, and cleaning and adjusting the carburator and that was about it. All you needed was a meter and a strobe light. Alas the days of the backyard mechanics are gone forever. Spark plugs last 100,000 miles, there are no points, distributors caps or rotors, no carburators to adjust. Everything is adjusted by a computor which looks at engine RPM, engine temperature, throttle position probably, and for all I know a lot of other parameters. You need a computer to override it and a special course to know how. My car which is 8 years old has 10 computers, some of which are horrifyingly mounted inside the front bumper. If the engine misfires even once, a yellow warning light tells you to see a mechanic and enters the event in a data logger. If it misfires twice in a row, you get a red warning light and are directed to shut the engine off and have the car towed. My friend who was a mechanic for a Lincoln Mercury dealer and who sadly passed away about 6 years ago had over $100,000 invested in tools and test equipment for his job. And that was just for Ford products. He was constantly in school attending courses on the latest repair techniques. Life is not so simple anymore.

[E-Stat]

Everything is adjusted by a computor which looks at engine RPM, engine temperature, throttle position probably, and for all I know a lot of other parameters.
A bunch more parameters, especially for performance oriented engines. The Honda ECU found on the wife's S2000 has additional sensors for manifold pressure, atmospheric pressure, crank position,oxygen, water temp, intake air temp, knocks, air/fuel mixture, and variable rate cam engagement. On their highest performance motorcycles with separate upper (so called showerhead) and lower fuel injectors, their engagement thresholds as well. They possess multiple 3-D horsepower/torque "maps" that optimize controls for varying performance requirements. That is how they achieve more than 100 bhp / litre.


You need a computer to override it and a special course to know how.
Or buy flexible aftermarket ECUs that are optimized for different conditions. Life may not be simple any more, but it sure can be more fun!

rw

[ruadmaa]

I was at the auto parts store buying wires for a tune up I was doing on my 93 ford ranger. There was 3-4 different options. The prices ranged from $12-50. I called my Porsche mechanic and asked him why. He said there was a big difference in the shielding of Rfa as the noises in a car could really screw with the electronic ignition. He also stated that the better cables gave you better gas mileage.

So what is everybodies take on this? And how does it add to the controversy?

The term "Spark Plug Wires" is a misnomer. Sparkplug cables are made out of graphite and designed to handle extremely high voltages. The quality of the spark plug cables that you put in your car will affect overall engine performance by delivering a better spark to the cylinders. Spark plug cables (unlike audio cables) do burn out and have to be replaced periodically. The higher quality cables you buy the longer they will last. Your mechanic was telling you the truth in regards to different qualities of spark plug cables.

Incidentally, if you were to actually use a wire in spark plug cables you would be putting out so much RF interference that your neighbors could not watch television.

[skeptic]

It's all coming back to me now. Yes that's right. And in that case, they can make a very big difference.

[mtrycraft]

It's all coming back to me now. Yes that's right. And in that case, they can make a very big difference.


Makes sense pumping in 60kv

[mtrycraft]

The term "Spark Plug Wires" is a misnomer. Sparkplug cables are made out of graphite and designed to handle extremely high voltages. The quality of the spark plug cables that you put in your car will affect overall engine performance by delivering a better spark to the cylinders. Spark plug cables (unlike audio cables) do burn out and have to be replaced periodically. The higher quality cables you buy the longer they will last. Your mechanic was telling you the truth in regards to different qualities of spark plug cables.

Incidentally, if you were to actually use a wire in spark plug cables you would be putting out so much RF interference that your neighbors could not watch television.


Thanks for the refresher course:)