NGK Conventional vs. Ruthenium Plugs

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My car with 4 cyl. non turbo 2.4L GEMA engine is due for its 3rd plug change next month at 90K miles. It came with OEM NGK conventional v groove nickel electrode plugs with 30,000 mile change interval (aka "copper" plugs). I'm itching to try the new Ruthenium plugs. This following 2014 thread with similar question has a high consensus of "only use OEM" for numerous reasons (i.e., best design/match for that engine/no performance gains, only longevity with precious metal): https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3354337/1 vs. Molakule's recent thread describes that fine wire plugs have better spark, maybe better combustion = better performance?: https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/5322738/spark-plug-tips#Post5322738 Which is it? OEM for this simple engine for best performance or something else? Plug change difficulty is NOT a concern. Cost difference is negligible IF I run the non OEM plugs 2x - 3x the OEM recommendation of 30K. Comparison: cost per 4 delivered (Rock Auto) V power.......... ZFR5F-11........$10.79........OEM 30K interval........Nickel center, nickel ground G power...........ZFR5FGP.........$12.87........40K? interval...............Platinum center, nickel ground Iridium IX..........ZFR5FIX-11......$28.67........40-50K interval...........Iridium center, nickel ground Ruthenium...... FR5AHX............$35.63........80-100+?interval.......Ruthenium center, platinum ground Laser Platium...PZFR5F-11......$40.31.........80-100 interval...........Platinum center, platinum ground Laser iridium not listed for this app. Thank you!
 
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If OE was "copper" and they are easy to change, my choice would be either the NGK G-Power or the Denso Iridum TT. The best case for ruthenium is on cars where the job is difficult and you never want to do it again. The whole point of ruthenium is longer service life
 
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Watertown, New York
I have pulled Ngk Laser iridium, and Denso long life iridium with 100k+ miles and still in decent condition. The Ruthenium are supposed to be better than Iridium, so I would give those a try. I just put Ngk Ruthenium in our Nissan quest van and they look to be a good plug.
 
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I guess what I'm asking is if Molakule's recent thread gives enough support that the fine wire plugs actually improve performance over large electrode conventional plugs. Not horsepower, but maybe better combustion, less emissions/better catalytic converter life, maybe a tad better mpg...maybe because the electrodes don't wear like the conventional plugs do - .044 new/ .055+ at 30K miles. Maybe less strain on the coil-on-plugs? Is there any possible negative impact using anything but OEM? Remember the old guys that claimed certain car brands ran best on only one brand plug? I.E. - Ford = Motorcraft, GM = ACdelco, Japanese car = Japanese plug, LOL.
 
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Canada
Originally Posted by D1dad
The ruthenium's are cheaper than laser iridium yet I can't figure out why.
Go price out the cost of iridium vs. ruthenium. Ruthenium = $250/ounce Iridium = $520/ounce
 
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I just put a set of Bosch Iridium in my '17 3.5 ecoboost. Definite increase in fuel mileage. As a side benefit, the threads on them are anti-seize.
 
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I put Denso Iridium TT's in our Van. I really like them vs laser iridiums. I also put Ruthenium's in my Mazda. Run's fine but it's only been 400 miles so Jury is still out on MPG increase or not.
 
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Originally Posted by pitzel
Originally Posted by D1dad
The ruthenium's are cheaper than laser iridium yet I can't figure out why.
Go price out the cost of iridium vs. ruthenium. Ruthenium = $250/ounce Iridium = $520/ounce
Maybe, but the ngk irridiums are $8 at AA compared to $20 for the lasers. Meanwhile the ruthenium's are a long life plug. When I did the wife's Murano I used laser because of the pita it was. I'll use cheaper plugs on my altima because a plug change on a 2.5 takes 15 minutes.
 
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N.H, U.S.A.
All plugs are copper - its for heat transfer away from the firing tip Regular plugs should be Inconel steel alloy or similar at the ground wire and tip There is absolutely NO QUESTION that fine wire Ir plugs have a lower misfire count and require less voltage to fire, They may also have less quenching. An Issue is on resonant negative fire systems - Ir don't fire "backwards" as well as a special dual platinum pill plug like Denso TT or the special ford part numbers for reverse fire. So If you have a distributor or a coil-on-plug ignition I would not hesitate to step up to an Ir fine wire plug. Its all about correct heat range at this stage. I would highly recommend the Autolites for good quality and low cost
 
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As is pointed out in the thread by Molakule, the effects of the "crisper" spark is an immediate breakdown of the molecules next to the spark, to their more reactive constituents, instantly firing them, and allowing better reactivity/combustability of the rest air/fuel mixture. This burns more of the charge. As we know the best gasoline engines are 35-45% efficient, so any increase in efficiency is good. As far as noticing the difference - some people do, some dont, as is expected when we are talking a few %. You can rest assured it is there.
 
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I don't see how an end user can claim to objectively see a couple percent change in mpg in the average car. Accordingly, I don't see how an end user can claim to _see_ an objectively reduced cost of ownership with high-$ spark plugs. It's just not visible. One has to accept the generality, and tell oneself that the generality applies in one's own specific case, but below one's ability to discriminate. As an end user, I put iridium plugs in my vehicle because I think it's better for combustion efficiency. Even if that only reduces my household's contribution to the yellow-brown cloud's growth by a 10th of a percent, it's worth it to me. I don't like breathing that. It's not healthy for anyone. As far as ruthenium vs iridium, to me it _sounds_ like ruthenium is a way to increase profits by lowering costs and selling a new buzz-word.
 
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Originally Posted by bulwnkl
I don't see how an end user can claim to objectively see a couple percent change in mpg in the average car. Accordingly, I don't see how an end user can claim to _see_ an objectively reduced cost of ownership with high-$ spark plugs. It's just not visible. One has to accept the generality, and tell oneself that the generality applies in one's own specific case, but below one's ability to discriminate. As an end user, I put iridium plugs in my vehicle because I think it's better for combustion efficiency. Even if that only reduces my household's contribution to the yellow-brown cloud's growth by a 10th of a percent, it's worth it to me. I don't like breathing that. It's not healthy for anyone. As far as ruthenium vs iridium, to me it _sounds_ like ruthenium is a way to increase profits by lowering costs and selling a new buzz-word.
If it's a less expensive metal and it can withstand more heat, why not use them?
 
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Whether the metal is more or less expensive determines the spark plug company's profit. Whether the price to me is higher or lower is what one would look at in terms of 'why not use them.'
 
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North Carolina
Originally Posted by jayjr1105
If it's a less expensive metal and it can withstand more heat, why not use them?
They are close, but the melting point of iridium( 4435F) is higher than ruthenium (4233f). Why use ruthenium, if iridium has a higher melting point? Iridium is $1400 and oz and ruthenium is $250 and oz. I'm sure the profit margin is much better if they can sell the ruthenium plugs at the iridium prices. If the plugs are easy to get to and you don't mind changing them, sure use non- precious plugs every 30k. But if you have a difficult to change vehicle i'd use iridium, I don't get the advantage of ruthenium other than its a higher profit margin for the company.
 
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Originally Posted by spasm3
Originally Posted by jayjr1105
If it's a less expensive metal and it can withstand more heat, why not use them?
They are close, but the melting point of iridium( 4435F) is higher than ruthenium (4233f). Why use ruthenium, if iridium has a higher melting point? Iridium is $1400 and oz and ruthenium is $250 and oz. I'm sure the profit margin is much better if they can sell the ruthenium plugs at the iridium prices. If the plugs are easy to get to and you don't mind changing them, sure use non- precious plugs every 30k. But if you have a difficult to change vehicle i'd use iridium, I don't get the advantage of ruthenium other than its a higher profit margin for the company.
Tungsten's melting point is over 10 thousand degrees, so why don't we have tungsten spark plugs? laugh Is ruthenium harder? Or does it have some other property that would make it last longer despite the lower melting point?
 
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Originally Posted by slacktide_bitog
Tungsten's melting point is over 10 thousand degrees, so why don't we have tungsten spark plugs? laugh Is ruthenium harder? Or does it have some other property that would make it last longer despite the lower melting point?
Do they last longer? Laser iridums are 100k.
 
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Chicagoland
Originally Posted by spasm3
Originally Posted by jayjr1105
If it's a less expensive metal and it can withstand more heat, why not use them?
They are close, but the melting point of iridium( 4435F) is higher than ruthenium (4233f). Why use ruthenium, if iridium has a higher melting point? Iridium is $1400 and oz and ruthenium is $250 and oz. I'm sure the profit margin is much better if they can sell the ruthenium plugs at the iridium prices. If the plugs are easy to get to and you don't mind changing them, sure use non- precious plugs every 30k. But if you have a difficult to change vehicle i'd use iridium, I don't get the advantage of ruthenium other than its a higher profit margin for the company.
MolaKule posted in another thread that ruthenium is more resistant to erosion. A spark plug also won't get anywhere near being that hot, so the slight difference won't mean much between the 2. "The more exotic refractory metal tips simply give you more tip life and less gap growth because they erode less during the 'plasma' phase of the spark. As of right now, Ruthenium seems to have the lowest erosion rate of all of the refractory metal center electrode tips. Next year, another more exotic metal or metal compound may be found that surpasses Ruthenium. shocked2 "
 
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I replaced the OEM spark plugs in all my vehicles to Denso Iridium TT 4 years ago. Here are my observations for all the vehicles: 1. Engine start-ups are quicker (by a large margin). 2. Fuel economy has increased (by a small %). 3. Fuel economy is more consistent (consistently better). Unscientific observations over the 4 years.
 
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I should also note: 4. Throttle response is crisper (very noticeable). 5. Increase in power (low end torque). Noticeable in the Fords and not so much in the 4Runner and Dodge Van.
 
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