FireDemonSiC

Has anyone used these? To my understanding they are pretty new and I was wanting to try some in my motor and see how they perform.

Accel claims that silver has excellent thermal AND electrical conductivity properties and that these plugs are extremely resistant to fouling. To minimize on the speculation wars, I'm going to put some numbers here on common spark plug materials vs silver:



Iridium:

Electrical Resistivity (@ 20 °C) 47.1 nΩ·m
Thermal Conductivity 147 W·m−1·K−1
Melting Point 4471 °F
Vickers Hardness 1760 MPa
Density 22.56 g·cm−3


Platinum:

Electrical Resistivity (@20 °C) 105 nΩ·m
Thermal Conductivity 71.6 W·m−1·K−1
Melting Point 3214.9 °F
Vickers Hardness 549MPa
Density 21.45 g·cm−3


Copper:

Electrical Resistivity (@20 °C) 16.78 nΩ·m
Thermal Conductivity 401 W·m−1·K−1
Melting Point 1984.32 °F
Vickers Hardness 369MPa
Density 8.94 g·cm−3


Silver (The moment We've been waiting for!):

Electrical Resistivity (20 °C) 15.87 nΩ·m
Thermal Conductivity 429 W·m−1·K−1
Melting Point 1763.2 °F
Vickers Hardness 251 MPa
Density 10.49 g·cm−3




Now, when you factor in all these numbers, it will define what makes a spark plug produce a hotter spark and not as important but still a great factor to take into consideration, how many miles it can efficiently produce that spark for.

The most obvious sparkly that everyone has probably noticed at this point is the electrical conductivity. Yes, you've probably noticed that platinum has the worst conductivity off all spark plug types, and is why alot of people here will actually recommend against using them vs a copper plug. In comparison, like accel claims, silver leads the pack and has the ability to produce a hotter spark than that of even copper. HOWEVER, with the melting point aside (If anyone's spark plug temperature ever hits even the lowest of the 4 metal's melting point at 1763F, you have much bigger pistons errr uhm fish to fry than melted spark plugs), it is time we face the dark side which comes in the form of density and vickers hardness...

Everyone here knows what density means. The amount of mass per unit volume. While this CAN come into play to determine an object's durability, what is more important here is the vickers hardness. The vickers hardness test measures the hardness of material by seeing how deep of an indentation can be made in that material with a diamond pyramid shaped indenter. Take a look at silver vs copper, and you will see that the marginal difference in density is negated by the notable difference in hardness. Simply put, silver is a less durable material, and every time the spark in a cylinder fires more atoms will be removed from the electrode tip (Thus slowly increasing the gap) than that of a copper plug.

Taking this into account along with the recommended change interval of copper plugs, I would guestimate that in your run of the mill TGO street/strip vehicle that sees chronic high RPMs anyone who uses these plugs would have to change them approximately every 10k miles.

Never-the-less, around $22 off fleabay for a quantity of 8 #576SS plugs doesn't sound like a bad deal to be the guinea pig.

I tried making all this information as factual as possible and TBH, I am still not sure where the "highly resistant to fouling" claim comes in. But that's why this is a forum and not a magazine. Thoughts everybody?

burnout88

Interesting numbers. The Silver does have the lowest resitance but not really by much from the cooper. I run the Accel copper shorty plugs and have been happy with them not sure the silver is going to make any kind of a difference based on those numbers.

FireDemonSiC

I run NGK coppers. My engine seems to like them. I'm going to give the Accels a shot though when I do the intake/injector swap.

Cosmik Debris

Well everybody except you apparently.

Density = mass / volume

i.e. mass per unit volume.

FireDemonSiC

Deleted

Cosmik Debris

Yeah, sorry, I didn't quite mean it to come out that way.

FireDemonSiC

No prob. Communication error.

mmadden55

Silver is the best conductor next to gold however given the voltage in spark plugs the difference is negligible. Iridium however absolutely will not corrode and melts at rediculously high temps. for a long lasting good plug that is the way to go.

91phoenix

iTrader: (5)

Keep us informed. I am sure others would like to hear about honest thoughts of these plugs also. I personally do not see much to gain there based on what the copper seems to show but I do not like making assumptions either. I feel that comparing against copper is the best and overall fairest way. I never really liked platinum and maybe now I know why.

FireDemonSiC

Right now would not be a great time to try this experiment. While my injectors don't have any MAJOR problems they tend to have mood swings where one minute the car will idle like It's fresh off the showroom floor and others it will be a tad rough around the edges with even a bit of misfiring detected while neutral revving.

After I do the intake and manifold swap, I'm going to grab a set of these plugs and gap them at .035". I then intend to pull the #1 plug out at every 1000 mile interval and report any gap increase until around 10k. TBH I only drive locally and it might take 2 - 3 years to hit the 10k mark if my motor ends up like these plugs, but I think it will be an interesting experiment none-the-less.

efiguy

iTrader: (2)

I've used them in 2 of my latest builds.
Tony Bischoff won last years EMC with them in, they claimed almost 10+hp increase with them.

calroc

Where do you, personally, stand on that "almost 10+hp" claim, being an Accel
Tech/distributor, & all? We've seen similar hp claims on spark plugs in the past. Seems a little doubtful. Actually, alot.

Richboll

So that's like a little over $2.00 per one horsepower...That's a deal!

FireDemonSiC

What he's saying is that just under a 2ohm difference in resistance between silver and copper plugs seriously does not add up to 10hp.

I could see possibly if we were talking about platinum vs silver, but even then 10hp is a pretty substantial claim for a spark plug.

efiguy

iTrader: (2)

I understand, that's why I said they. You'll have to talk to them to verify that but that's what I was told though I think it was even in the press release last year but again you'll need to check with them.

But please remember they made 700hp so 10hp is only about 1.5%.

Richboll

Sorry, while it may be a true claim, my tongue was firmly planted in my cheek.

FireDemonSiC

LOL I quoted the wrong post. When I first read it over again I was like wtf?

Richboll

Not a problem..In the future, I'll be a little more obvious with my skepticism.

burnout88

FireDemonSiC, did you try the silver plugs?

FireDemonSiC

Not yet. I have the whole top of the motor torn apart doing the manifold and portwork.

When I put everything back together I'll be putting them in.

burnout88

I just changed out my Accel copper shorty header plugs today. I noticed that they have changed the design on their new cooper shorty plugs. The old plugs had a u-groove cut into the electrode and the new design has eliminated that feature. Also the old plugs had screw off tips which were prone to coming loose and that has been eliminated. The ceramic is also a little thicker on the new plugs. I actually think the new Accel cooper shorty plugs are nicer quality then the old versions despite the elimination of the u-groove.

Also, the old plugs were made in Japan by Nippon Denso but the new plugs are made in the Czech Republic by a company called Brisk. Appears Accels is just rebranding Brisk's plugs.

Here is a link to the Brisk site and there silver plugs http://www.briskusa.com/products/spa...silver-racing/ . They look identical to the Accel plugs.

383RAT

I threw some in my motor because what I read about them sounded interesting and the cost wasn't much difference. So far I have only 40 miles on them so I can't tell you to much right now besides they seem to work fine. I'll be pulling number 1 plug in a month or two. I f I can remember I'll post if there is any problems.

Mystyk_Wynds

I have few interesting things to say, one for the record Sic Demon, you have some misinformation. Heat index in the plug has NOTHING to do with how hot a plug fires, and neither does the electro-conductivity of the material.
Heat index has two properties, the ceramic insulator thickness surrounding the center electrode, this determines how hot or cool the center electrode gets, and how fast it dissapates the heat.
Second, the strength of the spark is determined by the amount and type of resistance material incorporated into the main body of the plug between the two parts of the center electrode, this is based on conductivity of the said center material.
IE a silver plug with the same amount of resistor material will spark with more power, than a copper, steel, platinum, or iridium. But however this is not the case most of the time with plugs. A platinum or iridium plug has longer top half electrodes and less resistance material, so that the plug is comparable to steel, and vice versa for silver plugs, smaller center electrode with more resistor material.
Now you have to watch out for mixed breed plugs, this means that the top half of the plug is either aluminum or steel, then the bottom half of the electrode is only partially of that said material...Most commonly you find this with platinum, irridium, copper and silver.
Platinum or iridium fused tip...fine wire .5/.7mm tip to "focus" the spark....Think about it. It only makes some sense. Those tips are fused to steel electrodes, why? Becasue steel is better for conductivity, and only the tips actually need to be durable.
Another interesting thing, why are spark plugs not recycled? That is lot of unrecovered, irreplaceable, precious materials. Wasted money!!!.
Gold-$1680oz Silver-$31oz(Spark Plugs) Platinum-$1535oz(Catty) Palladium-681oz(Catty) Copper-$3.43oz (electrical) Iridium-$1050oz Rhodium-$1150oz (cats/spark plugs/jewelry). billions of dollars wasted, just in spark plugs.
Oh yeah just so you know, Ac Delco spark plugs...Are made by NGK. lol.

FireDemonSiC

Where in any of my posts did you see me indicate that plug material or heat index determines the strength of the spark? A "hot" spark is common lingo for a "strong" spark and that's the closest relation you're going to find.

Everything else you posted was pretty much re-iterating what I said.

Mystyk_Wynds

Sorry sic demon, I did in fact read it wrong. My bad. But most ppl associate "hotter" and "spark" with a stronger spark, when that is not always the case. An most plugs are based off a steel plug, being those were the first plug.
Now if someone wants to really see a difference is spark power, take a resistor plug and put it next to a non resistor plug. IE say a R45ts vs 45ts a non resistor plug shows the real power of a spark.
Ihave a set of 45ts right now, of which I'm converting over to a Krupa (Firestorm) style of plug.

Mystyk_Wynds

How come we don't combine metals say like copper or silver impregnated steel?