Installing Iridium IX plugs in 02' C32 tomorrow..What plugs & gap r you guys running?
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02' C32, '08 M6, '10 750LI, '06 993 turbo, 96' S600 V12 Coupe
Installing Iridium IX plugs in 02' C32 tomorrow..What plugs & gap r you guys running?
What plugs and gap are you guys running in your C32's? Going to put Iridium IX #5464 (bkr5eix-11) plugs in my 02' C32 tomorrow..My C32 is stock with K&N's..Thanks
Last edited by benzluvr1; Sep 6, 2009 at 03:48 PM.
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02 C32 AMG
you should search.......
and plugs and gap depend on your mods. if you're running more boost, you might want to go a step colder and change the gap. if stock, there is no need......and really, there is no need to change your spark plugs unless you're over 80K or so without a change or live in a rough climate
I'm running a heat range colder NGX IX Iridiums at a .034 gap. I'm running a range colder, again, because i'm running more boost than stock
and plugs and gap depend on your mods. if you're running more boost, you might want to go a step colder and change the gap. if stock, there is no need......and really, there is no need to change your spark plugs unless you're over 80K or so without a change or live in a rough climate
I'm running a heat range colder NGX IX Iridiums at a .034 gap. I'm running a range colder, again, because i'm running more boost than stock
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03 c32
Just like Josh, I am running the "7's", one range colder and gapped at .031 (per EuroTech).
The ones you are installing should be gapped at .034, especially considering you are not running any after market pulley.
The ones you are installing should be gapped at .034, especially considering you are not running any after market pulley.
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From: Diamond Bar, CA
W206 PHEV AMG
stock plugs are gaped at .039. if he doesn't have any mods why would .034 help?
I was reading what Splinter wrote on plugs gaping and reading some more.
here's from what I read
* narrow-gap risk: spark might be too weak/small to ignite fuel;
* narrow-gap benefit: plug always fires on each cycle;
* wide-gap risk: plug might not fire, or miss at high speeds;
* wide-gap benefit: spark is strong for a clean burn.
and from reading narrow-gap has worse mpg? also read that the reason for narrower gap is for those that are running 185 pulley which more boost = higher chance of spark getting blew out?
anyway, I've been running these NGK Iridium IX .039 plugs. I've gotten on avg less mpg then when I'm running Denso IK20 .040 plugs. BUT the iridium IX seems to be responding better/quicker?...OR it's just my imagination. I just did 228miles on 13gallon with majority highway miles. That avg only 17.5mpg. That's about 1mpg worse then what I was able to achieve before. I'm gonna put the IK20 (pulled then when I was diagnosing idle issue and they were all good still, so I saved'em) back and see what happens.
btw, don't know if the IK20 is colder plug then the iridium IX or if they have the same rating. wonder if that makes a difference in mpg.
Last edited by FrankW; Sep 6, 2009 at 04:48 PM.
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02 C32 AMG
anyway, I've been running these NGK Iridium IX .039 plugs. I've gotten on avg less mpg then when I'm running Denso IK20 .040 plugs. BUT the iridium IX seems to be responding better/quicker?...OR it's just my imagination. I just did 228miles on 13gallon with majority highway miles. That avg only 17.5mpg. That's about 1mpg worse then what I was able to achieve before. I'm gonna put the IK20 (pulled then when I was diagnosing idle issue and they were all good still, so I saved'em) back and see what happens.
btw, don't know if the IK20 is colder plug then the iridium IX or if they have the same rating. wonder if that makes a difference in mpg.
btw, don't know if the IK20 is colder plug then the iridium IX or if they have the same rating. wonder if that makes a difference in mpg.
Frank, what speed were you going on the highway? which it does matter obviously........with my heat range colder and .034 gap, i get about 25-26 when going 65 and 21-22 when going 75+......so your 17.5 if mostly highway sounds low to me......and i'm only running on 91 octane
as far as the Densos vs NGKs, the NGKs that i have are equivalent to the heat range colder - IK22s. IK20 is the stock heat range for the C32 and is not the same heat range that i'm running (despite all the NGK IXs being called thus, they have different part numbers denoting the different heat ranges).
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W206 PHEV AMG
i dont necessarily understand the whole narrow vs wide gap thing, but i dont like the sound of your gas mileage
Frank, what speed were you going on the highway? which it does matter obviously........with my heat range colder and .034 gap, i get about 25-26 when going 65 and 21-22 when going 75+......so your 17.5 if mostly highway sounds low to me......and i'm only running on 91 octane
as far as the Densos vs NGKs, the NGKs that i have are equivalent to the heat range colder - IK22s. IK20 is the stock heat range for the C32 and is not the same heat range that i'm running (despite all the NGK IXs being called thus, they have different part numbers denoting the different heat ranges).
Frank, what speed were you going on the highway? which it does matter obviously........with my heat range colder and .034 gap, i get about 25-26 when going 65 and 21-22 when going 75+......so your 17.5 if mostly highway sounds low to me......and i'm only running on 91 octane
as far as the Densos vs NGKs, the NGKs that i have are equivalent to the heat range colder - IK22s. IK20 is the stock heat range for the C32 and is not the same heat range that i'm running (despite all the NGK IXs being called thus, they have different part numbers denoting the different heat ranges).
about 50 of the rest 100miles were highway and 50 was local.
17.5 is the avg of 13 gallon covering 228miles.
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From: Texas
02' C32, '08 M6, '10 750LI, '06 993 turbo, 96' S600 V12 Coupe
I put em in tonite...Left em gapped about .036-.038...Close as I could get em...Picked up half a second 0-60..Happy with the results...Old plugs were rusty color and had little round white flat mounds on the ground (lower)electrode where the spark hits from the center(upper) electrode..Never seen that before, has anyone else seen that?...They were NGK-R with Mercedes logo on them.....Probably original..My C32 has 100k miles exactly so probably time to change em..
