Proper way to gap iridium plugs?

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I am seeing someone do it with this handy tool. is this the proper way to do it for iridium plugs?

https://youtu.be/q4Fg_Ve5EX4?t=105

Video starts 1-2 seconds before he shows.

I am getting NGK Iridium IX, I have heard some say that I shouldn't have to gap them, but if I do, is that the proper way? I know some folks say that you can damage the electrode if you do it wrong.
 
Originally Posted by Imp4
The proper way to gap them is to not gap them.

They will be good out of the box.


+2
 
From the video, in reference to using anti-seize on the threads, "the manual was printed in 2000 and spark plug technologies have changed" since then. Not so sure they've changed that much and I'm very, very certain that the metallurgy of the threaded portion of the plug hasn't. Plus, the metal on the engine where the plugs thread into absolutely hasn't changed !
 
Originally Posted by Imp4
The proper way to gap them is to not gap them.

They will be good out of the box.


yep. that is the proper procedure.. I do visually check them all to make sure one isnt a dud.

but you can mess them up checking the gap if you get a little happy.
 
I've gapped them with a wire gap gauge ,with a really really light touch no pressure when checking the gap. I under gap by .005 and i use anti seize on every plug even the ngk nickel plated.
 
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You can check them and if there just a little under leave them alone.
I always gap mine, i'll take them indoors and take my time doing it. I always find there off a little.
Some say there pre gapped but how can they be when that same plug will go in a lot of different engines.
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Originally Posted by Astro14
Originally Posted by Imp4
The proper way to gap them is to not gap them.

They will be good out of the box.


+2


+3 Many people get too anal with gaps. During service the plug gap will open up by 0.01 to 0.02 inches and will operate just fine. This is not you grampa's old black coil firing these plugs.
 
Originally Posted by rollinpete
Some say there pre gapped but how can they be when that same plug will go in a lot of different engines.
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That's exactly right.

New plugs are pre-gapped for the most common application. If the plug fits various engines, then it's a good chance the gap is going to be wrong.
 
In 60 plus years of gapping plugs i`m not changing out of respect to manufactures tolerances. That said the ignition systems of late seem to be very tolerant of a few thousants one way or other. Echo the light touch
 
Originally Posted by Snagglefoot
Well let's check. I see gaps at 0.040 to 0.044 inches for Iridiums. What other gaps are your owners manuals recommending for Iridium plugs? Not Platinums and certainly not Coppers.

'08 G35 with the VQ35HR engine and the FSM calls for Iridium plugs gapped at 0.043". The plug Nissan/Infiniti specs is FXE22HR11 and DENSO pre-gaps these at 0.044".
 
Originally Posted by hallstevenson
Originally Posted by Snagglefoot
Well let's check. I see gaps at 0.040 to 0.044 inches for Iridiums. What other gaps are your owners manuals recommending for Iridium plugs? Not Platinums and certainly not Coppers.

'08 G35 with the VQ35HR engine and the FSM calls for Iridium plugs gapped at 0.043". The plug Nissan/Infiniti specs is FXE22HR11 and DENSO pre-gaps these at 0.044".


Yep, .040 to .044. Waste of time to gap any thing in this range. It will naturally open up past 0.050 and the engine won't notice a difference.
smile.gif
 
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Originally Posted by rollinpete

Some say there pre gapped but how can they be when that same plug will go in a lot of different engines.
49.gif




Many/ most plug part numbers include the gap as part of the specification, so the engine design calls for that gap, heat range, reach, hex size, and that's about all.
 
i normally check the gap on one or two of the new ones i'm installing but very loosey so nothing is really damaging.

I check all the old plugs. I've seen some nearly twice the gap of what they should be and the car ran fine.
 
I have them in 3 out of 4 of my vehicles (don't make them for the F150). I don't gap them. Just check to see if they all look right (visual inspection).
 
Originally Posted by bowlofturtle

I check all the old plugs. I've seen some nearly twice the gap of what they should be and the car ran fine.


The spec for new plugs (particularly copper ones) assumes some growth, and perfection is somewhere in the middle of the service range.
 
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