today i went to this parts store, and i got some NGK Iridium, when he got it for me..i asked him if he has a gapping tool...then he told me that Iridium can't be gapped.
he said it can't because its too hard to gap...so i said its ok...and i left..

Is this true?
...and...
lets say, that if i do put the plugs in without it gapped...can i take it out and gap it?

 

They can be gapped for sure. How could they not? All you do when gapping is press the top metal peice closer to the electrode.

 

They can be gapped but they are very easy to ruin so you have to gap them correct and very very carefully. The biggest issues that I see is people go use the POS round gapping tool that isn't correct in the first place and this will ruin the tip of the plug and give you a misleading gap measurement. Only use a feeler gauge and bend the strap over the tip very carefully, you do not what to put any pressure on the iridium tip what so ever if possible.

 

ok..thanks

 

does anyone know the correct gapping for a one step colder NGK Iridium? Is it .25?

 

thats the best way to do it.

 

don't gap them. there is a good reason why. they come pre calibrated, you could blow the ceramics around it if you gap them, it's happened before. or worst, break the top metal part off.

but if you do it, just don't touch the electrode, iridium.

 

Don't say things if you're not possitive what you're talking about. I've been running the 1 step colder iridiums for awhile now. Since my HP numbers have gotten higher, I noticed some mis-fire at WOT. I removed each plug and gapped them all from the .032 the come at to .025 and now have no problems. The car runs better than ever...just by gapping the plugs correctly.

 

Just get the gapping tool and check the gap. i have iridium plugs and they came pre gapped. They can be adjusted but like ppl are saying - do be careful. I check my gap every time i go to the drag strip just to make sure.

 

I have the NGK one step colder's. SHould I have them gapped to .032??? I see that they come at .025 but is every car different?? It seems to run fine now with the .025 but I don't want a misfire later.

 

If things are find at .025 I would leave them at that. If you car isn't having trouble at low rpms I would leave the gap where it is. The only time I regap them is if you get misfire at higher rpm.

 

Will the misfire throw a CEL or will the misfire be just some sputtering of the car at higher RPM's? Just want to make sure I know what I am looking for in case it does happen.

 

If the misfire is very bad and happends repeatedly it will throw a cell. If it happens once it will not. Once it gets bad you will know it and be able to feel it. And this is what you will see first with incorrect plug gap.

Once you start to get to the limits of the ignition system due to power after a turbo upgrade or high limits of the stock turbo with alky injection it is a little bit harder to tell becuase it doesn't just misfire plainly its more like the spark isn't hot enough to keep things burning correctly so you need a fast data log to see rpms drop while accelerating because it is a littler harder to feel in the seat. I don't know if this will always throw a cell but I have seen some cars get away with no evidence of it showing up on the stock ecu.

Just my experience, hope it helps.

 

That's funny, i run the ngk bpr7iex, with the gap it came with and I run fine without any problems.

i guess you're running bpr8iex?

I'm personally not positive, but most of the tuners I talked to say no don't gap it.

That's all i'm saying. calm down.

Here is what I know, and I will explain it to you the best I can why you shouldn't gap iridium plugs.

iridium ones come pre-gapped for a reason. The reason is that the electrodes are pre-calculated to perform at their best at the calibrated distance without heating the electrode too much to cause pre-ignition.

Pre-ignition is what you'll be risking with gapping a iridium plugs. Smaller you go, hotter you make the insulators and the ignition tip.

You want to remove heat and ignite a/f. This is the purpose of your plugs.

only reason you're back-firing with the bpr8iex or the 1 step colder plugs are because they are 1 step colder and may not ignite causing the left over fuel to back-fire out of the exhaust. not quite mis-fire but maybe not ignite harder (?)

So by gapping the 1 step colder plugs, you're basically defeating the whole purpose of getting a 1 step colder plugs. You're not only risking detonation/pre-ignition but you're making it perform just like the stock heat range plugs or worst, 1 step hotter range plugs.

and maybe you're not back-firing anymore because you're getting knocks and detonation/pre-ignition.

I would personally back-fire (running rich) rather than pre-ignite.

That's my explanation. I'm not 100% sure, because there are some gaps in my explanation, but 98% of it is true.

I think you're contradicting yourself by asking me to not say it when I don't know, while you're just saying things because you think your car runs fine with it gapped.

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