This is topic Are my NGK Iridiums bad? in forum Tech Talk at Northern California Ford Owners  .


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Posted by J's DDLY SNK (Member # 2016) on :
 
I was told that these are to be installed as is straight from the box, no gapping is required, and that gapping would actually damage the plugs. Is this true? Because if it is, there goes $80 down the tube!!
 

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Posted by st5150 (Member # 51) on :
 
If you're NA, I wouldn't worry about it too much
 

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Posted by rob (Member # 50) on :
 
i would imagine the iridium is very brittle and gapping could destroy the electrode very easily

i have never EVER witnessed an NHRA or NASCAR team gapping plugs, they take 'em outta the box and torque 'em in...

if they are damaged, it will be obvious due to misfire...
 

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Posted by Black94 5.0 (Member # 655) on :
 
It should say on the end of the box what the gap is set to, from NGK....(Should be- .054" for a 97 Cobra)

Try to put the gap back to what it says on the box or whatever NGK recommends...The gap recommended is what NGK had the best results with..

Check and see if you damaged the electrode with the gapper, but you probaly didnt..

Good luck!
 

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Posted by st5150 (Member # 51) on :
 
Just some good reading on a similar topic:

http://www.alternativeauto.com/waterbox/wb-archives/sparkplugs.html
 

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Posted by rob (Member # 50) on :
 
the sharpness is where the denso plugs excel with a 1.5 mm electrode diameter!

nice link if a bit non-technical
 

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Posted by st5150 (Member # 51) on :
 
rob- I like the Alternative Auto articals because he explains everything so non-technical, but the technical backing and unbias dyno and track testing is all there. Everything from their story on traction, to cam selection, limits of various short blocks, ect is all well written, documented, tested and proven. Keep in many of these articals are up to 5+ years old. Many were denounced at the time, but have proven to be true... Alternative Auto was just ahead of its time
 

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Posted by J's DDLY SNK (Member # 2016) on :
 
Thanks for the responses. I think Rob is right. A few friends have told me( a bit too late ) that gapping would damage the electrode. At first the car ran great, all through the R's it ran smooth. Now 3 months later after 5,000 RPMs the car bogs a bit. I think if I try to reset the gapping I'll just damage them more. I guess its time for some new plugs. Again
 

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Posted by Blown Mystic (Member # 476) on :
 

quote:

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Originally posted by Black94 5.0:

Try to put the gap back to what it says on the box or whatever NGK recommends

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no that will just damage it more
 

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Posted by Rev Happy (Member # 661) on :
 
I had NGK TR55IX Iridiums on my N/A 96 Cobra and on the box it clearly said "no need to adjust spark plug gap due to extremely fine electrode" There's basically no need for gapping iridium plugs because the resistance of that tiny electrode is so small that the ignition system will overcome gap difference anyway.

Messing with the electrode basically gave them a shorter life...lol Just pull the plugs out and put some new ones in...

For the record, I just changed from the NGK Iridiums (had them in for about a year) to some Autolite 764s and the car runs just as well as it ever has... The Autolites will most likely not last as long, but they are a hell of a lot cheaper than what I paid for the NGK's ($6.95 a plug)...

[ March 22, 2003, 08:45 PM: Message edited by: Rev Happy ]
 

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Posted by Black94 5.0 (Member # 655) on :
 

quote:

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Originally posted by Blown Mystic:

quote:

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Originally posted by Black94 5.0:

Try to put the gap back to what it says on the box or whatever NGK recommends

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no that will just damage it more

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quote:

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Originally posted by bunchmyfunky:
Get the NGK copper Plugs TR55s, You will get great performance out of them and there only a $1.35 or so each.

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How do they compare to the Iridiums, besides the price. Do they perform better for a shorter time is that why they are so cheap. The Iridiums are suppose to last me 15,000 miles at least if not more. How long do the copper ones last?
 

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Posted by J's 4AXLR8N (Member # 2011) on :
 
Dude, stop buying the cheap shit, spend some money and get some good stuff. J/k
 

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Posted by Rev Happy (Member # 661) on :
 

quote:

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Originally posted by J's DDLY SNK

How do they compare to the Iridiums, besides the price. Do they perform better for a shorter time is that why they are so cheap. The Iridiums are suppose to last me 15,000 miles at least if not more. How long do the copper ones last?

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I guess you must have missed my post...

quote:

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Originally posted by Rev Happy

For the record, I just changed from the NGK Iridiums (had them in for about a year) to some Autolite 764s and the car runs just as well as it ever has... The Autolites will most likely not last as long, but they are a hell of a lot cheaper than what I paid for the NGK's ($6.95 a plug)...

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quote:

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Originally posted by bunchmyfunky:
The performance from a copper plug is great. They will need to be replaced every 20k miles or so.

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Do you recommend gapping them at stock .54 or something different? and thanks for the info
 

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Posted by bunchmyfunky (Member # 360) on :
 
I left mine at stock.
 

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