bosch Iridium plugs any good?
- Thread starter hooligan24
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I almost always have problems running Bosch spark plugs on cars that never were equipped with Bosch plugs at the factory.
If you want an iridium plug, get one that was made by the same company that made your OEM plugs.
Also, how can platinum or iridium plugs be bad for forced induction when nearly everything made after the year 2000 had them? That would only make sense to me if the vehicle was originally equipped with copper spark plugs.
If you want an iridium plug, get one that was made by the same company that made your OEM plugs.
Also, how can platinum or iridium plugs be bad for forced induction when nearly everything made after the year 2000 had them? That would only make sense to me if the vehicle was originally equipped with copper spark plugs.
Iridium and platinum are not very good conductors of electricity, combine that with the increased cylinder pressures of forced induction and it can put a strain on the ignition system. The only real benefit of iridium or platinum plugs is long life, because they are wear resistant and don't oxidize. The melting point is irrelevant, because if you are melting a standard electrode something is wrong.
Originally Posted By: AVB
Iridium and platinum are not very good conductors of electricity, combine that with the increased cylinder pressures of forced induction and it can put a strain on the ignition system. The only real benefit of iridium or platinum plugs is long life, because they are wear resistant and don't oxidize. The melting point is irrelevant, because if you are melting a standard electrode something is wrong.
The melting point is NOT irrelevant, how do you think electrode erosion occurs ? It is a combination of the combustion heat (and gasses) and the electrical spark heat.
Modern electrical systems are not strained by the small difference in resistance of electrodes. Electrode wear and the increased electrical "resistance" due to an increased air gap has a much greater affect.
Iridium and platinum are not very good conductors of electricity, combine that with the increased cylinder pressures of forced induction and it can put a strain on the ignition system. The only real benefit of iridium or platinum plugs is long life, because they are wear resistant and don't oxidize. The melting point is irrelevant, because if you are melting a standard electrode something is wrong.
The melting point is NOT irrelevant, how do you think electrode erosion occurs ? It is a combination of the combustion heat (and gasses) and the electrical spark heat.
Modern electrical systems are not strained by the small difference in resistance of electrodes. Electrode wear and the increased electrical "resistance" due to an increased air gap has a much greater affect.
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Here is a quote about spark plug electrode wear:
"The electrode wears from the locations that discharge easily with spark discharge.
In particular, since the center electrode reaches high temperatures, it oxidizes and wears.
The amount of electrode wear varies with the electrode material melting point, strength, hardness, etc. In order to reduce the amount of this wear, nickel alloys, platinum, iridium, and other such materials are used for the electrodes and service lives are also extended with fine electrodes."
Here is a quote about the "air" gap affects:
"The required voltage (the voltage required to discharge across the gap) rises in proportion to the distance driven.
This rise in the required voltage is large until the sharp section at the end of the center electrode is worn round to some degree (about 4,000km). After that, the main factor is the enlargement of the gap due to electrode wear and the rise in the required voltage is smaller."
"The electrode wears from the locations that discharge easily with spark discharge.
In particular, since the center electrode reaches high temperatures, it oxidizes and wears.
The amount of electrode wear varies with the electrode material melting point, strength, hardness, etc. In order to reduce the amount of this wear, nickel alloys, platinum, iridium, and other such materials are used for the electrodes and service lives are also extended with fine electrodes."
Here is a quote about the "air" gap affects:
"The required voltage (the voltage required to discharge across the gap) rises in proportion to the distance driven.
This rise in the required voltage is large until the sharp section at the end of the center electrode is worn round to some degree (about 4,000km). After that, the main factor is the enlargement of the gap due to electrode wear and the rise in the required voltage is smaller."
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Originally Posted By: hooligan24
I normally use NGK V-POWER 4306's(around $2.50 a plug), as do most SRT4 owners. Stock plugs are Champions. I was interested in going Iridium since it seems these motors beat up on the V power plugs. They run good, but seems like I need to change them out every 10-15k miles to keep the engine running smooth.
At $4 a piece after rebate on the Bosch Iridiums, I just had to ask the forum about your take on these plugs. So far, its not looking good
I could only WISH that my plugs were as downright EASY to change out as yours are (in the SRT4)!!!
IF they were, I would just use the V Powers and be MORE THAN ECSTATIC to change them out every 5K miles if I had to.
Since it is a 4 hour ordeal for my car/engine bay, and my hands/arms look like I went 1000 rounds with a rabid/insane Wolverine when I'm finished, I am FORCED to use NGK/Denso, or Delco Iridiums.
I normally use NGK V-POWER 4306's(around $2.50 a plug), as do most SRT4 owners. Stock plugs are Champions. I was interested in going Iridium since it seems these motors beat up on the V power plugs. They run good, but seems like I need to change them out every 10-15k miles to keep the engine running smooth.
At $4 a piece after rebate on the Bosch Iridiums, I just had to ask the forum about your take on these plugs. So far, its not looking good
I could only WISH that my plugs were as downright EASY to change out as yours are (in the SRT4)!!!
IF they were, I would just use the V Powers and be MORE THAN ECSTATIC to change them out every 5K miles if I had to.
Since it is a 4 hour ordeal for my car/engine bay, and my hands/arms look like I went 1000 rounds with a rabid/insane Wolverine when I'm finished, I am FORCED to use NGK/Denso, or Delco Iridiums.
Originally Posted By: Corvette Owner
Originally Posted By: mechtech2
If you love copper so much, why not get copper iridiums?
Do you know where the copper is, and what it does?
No such thing. The copper/iridium is used in the electrode.
Copper melts at 1983 F compared to Iridium at 4440 F !
No such thing??
Copper is usually in the core, and there ARE copper plats and iridiums.
Yes, there are a few that had copper through the tip.
A short life design.
And they are unsuitable for 'waste spark' ignitions.
Originally Posted By: mechtech2
If you love copper so much, why not get copper iridiums?
Do you know where the copper is, and what it does?
No such thing. The copper/iridium is used in the electrode.
Copper melts at 1983 F compared to Iridium at 4440 F !
No such thing??
Copper is usually in the core, and there ARE copper plats and iridiums.
Yes, there are a few that had copper through the tip.
A short life design.
And they are unsuitable for 'waste spark' ignitions.
Originally Posted By: Corvette Owner
The melting point is NOT irrelevant, how do you think electrode erosion occurs ? It is a combination of the combustion heat (and gasses) and the electrical spark heat.
Modern electrical systems are not strained by the small difference in resistance of electrodes. Electrode wear and the increased electrical "resistance" due to an increased air gap has a much greater affect.
I believe corroision and oxidation along with wear resistance have more of an effect on erosion than melting point.
In this application the ignition system is dealing with firing two plugs at once with high cylinder pressures and 0.050 recommended spark plug gap. I think the manufacturer recommends standard plugs for a reason.
I made a mistake earlier, iridium is a better conductor than I realized. It is not a good conductor but is better than nickel which is better than platinum. But we are dealing with alloys so that alters the conductivity also.
The melting point is NOT irrelevant, how do you think electrode erosion occurs ? It is a combination of the combustion heat (and gasses) and the electrical spark heat.
Modern electrical systems are not strained by the small difference in resistance of electrodes. Electrode wear and the increased electrical "resistance" due to an increased air gap has a much greater affect.
I believe corroision and oxidation along with wear resistance have more of an effect on erosion than melting point.
In this application the ignition system is dealing with firing two plugs at once with high cylinder pressures and 0.050 recommended spark plug gap. I think the manufacturer recommends standard plugs for a reason.
I made a mistake earlier, iridium is a better conductor than I realized. It is not a good conductor but is better than nickel which is better than platinum. But we are dealing with alloys so that alters the conductivity also.
Looking at my cars one could take a good guess. The four old Fords use OEM Autolite BF42 as I have a large stash. The Dodge uses OEM Champion. The Mazda uses NKG. The two newer Fords use Motorcraft as specified. Those two are very particular about their plugs. Anything else causes stumbles on quick acceleration. None, of course, are iridium.
I went ahead and ordered the plugs. I have been using the NGK 4306's long enough that I should be able to feel if the Bosch plugs change the way the engine runs. I dont run the car around the race track anymore, and I have never drag raced it. I use the car for daily driving a 22 miles round trip to and from work. I rarely get on the gas pedel anymore, but I could do a couple of pulls to see how they run at the stock gap of .050. I run the 4306's at .040.
hooligan.....I just looked up the specs on your Dodge Neon SRT-4. Very impressive!!!!!
^^^Yes, do not diss the jellybeans, they are for real.
I've been too pleased with the performance of the NGK 4306 (LZTR5A13) to bother.
I read somewhere that the Mopar Stage II kit specs NGKs instead of Champions.
The O'Reilly countermonkey gave me a hard time about Champions being the "right" plug last time. Looked at his screen and he had a VIN B N/A 2.4 pulled up even though I told him it was a GT Turbo VIN G. I tried Champions and I don't like 'em. Plus they would have been 1 step hotter and would have been even further from .050 for me to gap.
You might get a longer service life, but the SRT/4's plugs are easy enough to change. I don't think you'll see any measurable performance gains
I read somewhere that the Mopar Stage II kit specs NGKs instead of Champions.
The O'Reilly countermonkey gave me a hard time about Champions being the "right" plug last time. Looked at his screen and he had a VIN B N/A 2.4 pulled up even though I told him it was a GT Turbo VIN G. I tried Champions and I don't like 'em. Plus they would have been 1 step hotter and would have been even further from .050 for me to gap.
You might get a longer service life, but the SRT/4's plugs are easy enough to change. I don't think you'll see any measurable performance gains
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