Is iridium IX or laser iridium better?

The Maintenance thread is a little vague about the difference between the two, other than that the Laser Iridium's last longer. Research on the net shows they are also dual metal surface (as opposed to just one on the Iridium IX's).

So, seeing as how I'm interested in improving my MPG first and foremost, which are better NGK's to go with?

(And on a side note: Is there actually a discernible difference to the lay person in terms of performance between the two? Will the average, non-mechanically inclined person like myself actually "feel" a better driving experience from one set of plugs over the other?)

Go with the laser iridium. The IX only last half the amount of miles or the Laser, so you replace them at a faster rate. Even if the IX produce better gas mileage than the Laser (which would be very difficult to measure) it wont make up for cost of replacing them twice in the same amount of time as the Laser iridium's. The IX is more of a performance plug, which is the opposite of the corolla. Denso makes good plugs too if you are interested in that.

The Iridium IX like the Denso Iridium power are "power" plugs meaning they put out a slightly stronger spark at the expense of shorter life because they do not have a platinum ground strap (making it dual precious metal). They also have an ultra fine wire versus the fine wire of the others.

The Iridium IX are about 2-3 dollars per plug cheaper depending on the source.

I have used them before and noticed zero difference versus Denso Iridium Long Life.

For the price they are good. But if you plan to keep the plugs for 120K then go with Denso Iridium Long Life or NGK Laser Iridium.

Quick question:

I've heard that plain copper plugs produce better power and mileage versus the longlife ones.

Any truth to that?

I'd rather get better engine performance and change more often than longer life out of the plugs.

Copper plugs are the best initially but increase gap much faster. This increased gap put loads of stress on the individual coils and will likely cause them to blow out.

Even with a copper plug you will likely not notice any differences in running. Just run a factory or "power" plug and save yourself damage, time, and threads (from constant changes) in the head.

I'm currently using Denso Platinum TT and have had no problems.

I have 70k on my NGK LASER IRIDIUMS. Should I change them out or are they fine for a while?

I used the NGK IFR5T11's in mine. They should be good for 120k just like the OEM's. Right now I have half their life on them (60k) and the car still runs perfectly and fires right up.

I used the NGK IFR5T11's in mine. They should be good for 120k just like the OEM's. Right now I have half their life on them (60k) and the car still runs perfectly and fires right up.

FYI: here is a picture of my ngk Laser Iradiums with about 72k on them.......I just installed new ngk eix's

Hard to see from the picture... They look good? Haven't pulled mine since installing.

Hard to see from the picture... They look good? Haven't pulled mine since installing.

on my phone I can Zoom in on it. They are not good. The ground electrode is worn out at an angle.

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I used the NGK IFR5T11's in mine. They should be good for 120k just like the OEM's. Right now I have half their life on them (60k) and the car still runs perfectly and fires right up.

if you can change them yourself i think I would do it before 80k for $27 and 45 minutes of your time......IMHO

...doesn't that usually mean you have a lean condition? Did you gap them before inserting?

...doesn't that usually mean you have a lean condition? Did you gap them before inserting?

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Could be because of lean Condition. Not sure. I had a bad o2 sensor for a month or so a few years back. No other issues. I gapped them @.044. The one's I took out were @ .043

What caused you to replace them so early? Did you have a misfire? Were they worn evenly?

Also, no offense, but when you gapped them, did you touch the electrode at all? As you know they are very fragile since the iridium is only a very thin plating over the base metal (nickel in your case, platinum in mine). I have been told to not touch them at all, not even to put a gauge against them.

Why not go for the IFR's again instead of the EIX's? I believe the IFR's are rated for about twice the mileage the EIX's are, even though NGK no longer has that info on their website.

http://www.ngk.com/ngk-aut-c1411.aspx

They still show a bar graph where the IFR's have "more than double" the lifespan of the EIX's (4.5 "bars" instead of 2).

Honestly I'm inclined to let mine go another 100k+ like the OEM's before replacing because my car runs like a top right now and when I yanked the originals at 105k they looked almost brand new, but if you think there is something wrong with the IFR design that is causing premature wear, that would be interesting to hear more about since this is the first I've ever heard of this. The pastor of my church has an '05 Camry and he said he let his OEM plugs go 150k before they finally misfired forcing him to replace them (not what I would have done, I have to say).

What caused you to replace them so early? Did you have a misfire? Were they worn evenly?

Also, no offense, but when you gapped them, did you touch the electrode at all? As you know they are very fragile since the iridium is only a very thin plating over the base metal (nickel in your case, platinum in mine). I have been told to not touch them at all, not even to put a gauge against them.

Why not go for the IFR's again instead of the EIX's? I believe the IFR's are rated for about twice the mileage the EIX's are, even though NGK no longer has that info on their website.

http://www.ngk.com/ngk-aut-c1411.aspx

They still show a bar graph where the IFR's have "more than double" the lifespan of the EIX's (4.5 "bars" instead of 2).

Honestly I'm inclined to let mine go another 100k+ like the OEM's before replacing because my car runs like a top right now and when I yanked the originals at 105k they looked almost brand new, but if you think there is something wrong with the IFR design that is causing premature wear, that would be interesting to hear more about since this is the first I've ever heard of this. The pastor of my church has an '05 Camry and he said he let his OEM plugs go 150k before they finally misfired forcing him to replace them (not what I would have done, I have to say).

good questions.........I should have just got the Laser ones again......I did not realize the large difference in life span and I thought the eix would give me more power.....I made a mistake not getting the Lasers again......but hey if the cars last me to 222,000 miles(40k on the EIX) I will swap them out again........the car was running a little rough and it lost some power.........I have an AWD Vibe and the HP is very low because the exhaust has to be run all around the driving gear......the thing is slow.........

Don't take my advice .. about these cars....there are a lot of smart people on this forum that know more then I do.........My daughter will have the car in college next summer and it is about 7 hours away.....I want to do whatever maintence I can before then.......

I did touch the electrode when I gapped them......I hope it is not an issue...not sure how you would do it if you cant touch them......

NGK's IFR and EIX should already be gapped to 1.1mm (0.0433 inch), which is why their number ends in "11". If you ever do gap them out, pry up the ground electrode from the sides without touching its tip area or the fine center electrode... I had a set of EIX, and the gap had increased to 1.25mm with 90,000 miles on them, mostly from ground electrode wear. I now run Bosch Platinum Ir (iridum) Fusion plugs with 4 yttrium-enhanced ground electroes. They are excellent and last even longer.

http://www.boschautoparts.com/sparkplugs/pages/platinumirfusion.aspx

NGK's IFR and EIX should already be gapped to 1.1mm (0.0433 inch), which is why their number ends in "11". If you ever do gap them out, pry up the ground electrode from the sides without touching its tip area or the fine center electrode... I had a set of EIX, and the gap had increased to 1.25mm with 90,000 miles on them, mostly from ground electrode wear. I now run Bosch Platinum Ir (iridum) Fusion plugs with 4 yttrium-enhanced ground electroes. They are excellent and last even longer.

http://www.boschautoparts.com/sparkplugs/pages/platinumirfusion.aspx

Are my plugs damaged if I touched them with the metal gap tool?

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Possibly, but probably not substantially... It depends on exactly how you did it. Did you have a good look at them before installing? Did you mushroom and/or bend the center electrode? Did you dull out the ground electrode's sharp edges? What did the gap seem to be at before you adjusted them?

Possibly, but probably not substantially... It depends on exactly how you did it. Did you have a good look at them before installing? Did you mushroom and/or bend the center electrode? Did you dull out the ground electrode's sharp edges? What did the gap seem to be at before you adjusted them?

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I did not change the gap. I just slipped in my coin shaped gap tool and saw that it was close to the proper cap. I looked at the plug as I put the anti seize on. I think they were fine