They are copper core plugs
NGK TR55 Question
Thread Starter
Burning Brakes
Joined: May 2003
Posts: 990
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From: Germantown TN
NGK TR55 Question
I am curious if anyone has used the TR55's that are part number 3951. I grabbed 8 of these for my header install and they were all about $1.70 a piece. They ended up not being copper like the ones I used in the past but I installed them anyway because it was all that I had. Am I using the wrong plugs in my car?
Safety Car
Joined: Sep 2000
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From: Tampa, FL
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I am curious if anyone has used the TR55's that are part number 3951. I grabbed 8 of these for my header install and they were all about $1.70 a piece. They ended up not being copper like the ones I used in the past but I installed them anyway because it was all that I had. Am I using the wrong plugs in my car?
Thread Starter
Burning Brakes
Joined: May 2003
Posts: 990
Likes: 0
From: Germantown TN
Well my Tr55's don't look like they are copper plugs. I have gapped them at 50 in the past in my other cars but this time I left the gap alone. I was told several people have run them without having to regap. Should I pull them all and regap?
Le Mans Master
Joined: May 2006
Posts: 5,987
Likes: 18
From: DuBois PA
St. Jude Donor '11-'12-'13-'14-'15
The 3951s are copper core plugs and come pre-gapped at .055". The NGK website recommends a gap of .050"...
Double Platinum 7862 PZTR5A-15 0.050
IX iridium 7164 TR55IX 0.050
GP platinum 3403 TR55GP 0.050
V-power 3951 TR55 0.050
I left my gap @ .055" FWIW...
Double Platinum 7862 PZTR5A-15 0.050
IX iridium 7164 TR55IX 0.050
GP platinum 3403 TR55GP 0.050
V-power 3951 TR55 0.050
I left my gap @ .055" FWIW...
Le Mans Master
Joined: Aug 2005
Posts: 5,375
Likes: 328
From: CA.
St. Jude Donor '13-'14-'15
YES they are copper plugs--but the key word is "core"they are copper core plugs---meaning the copper is in the center or "core" of the plug
Last edited by tblu92; Apr 25, 2007 at 04:09 AM.
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