E3 spark plug
Postmaster
Joined: May 2008
Posts: 2,703
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From: La Vergne, TN
uh its not a 5.0. its a beefed up 351W HO. with a cam and ported heads.
Hotshot
Joined: Sep 2001
Posts: 11,958
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My 95 has about 275k on the original drivetrain. I always run Motorcraft or Autolite platinums and it doesn't miss. I have had good luck with the platinum plugs lasting longer. I know most feel that the coppers work better and thats what I usually recommend going with.
Posting Guru
Joined: Nov 2008
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From: Pennsylvania Wilds
My 95 has about 275k on the original drivetrain. I always run Motorcraft or Autolite platinums and it doesn't miss. I have had good luck with the platinum plugs lasting longer. I know most feel that the coppers work better and thats what I usually recommend going with.
Senior User
Joined: Aug 2007
Posts: 346
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From: Bristol/Hartford CT
I know it wasn't I was just saying in general. I've seen a lot of these older SBF's with that slight miss at idle.
Posting Guru
Joined: Nov 2008
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From: Pennsylvania Wilds
I know; I made it! 
I oil the threads when I change them, just in case, but I still worry about it.
Which reminds me... I didn't oil the threads when I put plugs in my friend's Firebird that we're rebuilding... Ah well, I was afraid to tighten them in much as it was, I think I started stripping threats turning one in by hand... Silly aluminum heads...
I oil the threads when I change them, just in case, but I still worry about it.
Which reminds me... I didn't oil the threads when I put plugs in my friend's Firebird that we're rebuilding... Ah well, I was afraid to tighten them in much as it was, I think I started stripping threats turning one in by hand... Silly aluminum heads...
Lead Driver
Joined: Nov 2002
Posts: 9,555
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From: Concord, NC
I oil the threads when I change them, just in case, but I still worry about it.
Senior User
Joined: Dec 2009
Posts: 374
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From: Portsmouth, Va
I use OEM. Motorcraft Coppers. Torqued down to spec. No oil on threads, no anti-seize. I don't drive the truck tons of miles so I'll have to decide when I want to swap them out.
Copper is a better electrical conductor than platinum. The only reason platinum is used is cause it's stronger than copper so lasts longer. It is not a better conductor. The car buyers want as few maintenance intervals as possible, which is why platinums were used. I won't use them unless they are what came in the vehicle. IE my Supra came with NGK platinums and that's what it will get.
Copper is a better electrical conductor than platinum. The only reason platinum is used is cause it's stronger than copper so lasts longer. It is not a better conductor. The car buyers want as few maintenance intervals as possible, which is why platinums were used. I won't use them unless they are what came in the vehicle. IE my Supra came with NGK platinums and that's what it will get.
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Posting Guru
Joined: Nov 2008
Posts: 1,183
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From: Pennsylvania Wilds
I use OEM. Motorcraft Coppers. Torqued down to spec. No oil on threads, no anti-seize. I don't drive the truck tons of miles so I'll have to decide when I want to swap them out.
Copper is a better electrical conductor than platinum. The only reason platinum is used is cause it's stronger than copper so lasts longer. It is not a better conductor. The car buyers want as few maintenance intervals as possible, which is why platinums were used. I won't use them unless they are what came in the vehicle. IE my Supra came with NGK platinums and that's what it will get.
Copper is a better electrical conductor than platinum. The only reason platinum is used is cause it's stronger than copper so lasts longer. It is not a better conductor. The car buyers want as few maintenance intervals as possible, which is why platinums were used. I won't use them unless they are what came in the vehicle. IE my Supra came with NGK platinums and that's what it will get.
Posting Guru
Joined: Mar 2007
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One thing to think about in regards to platinum, iridium, and copper plugs is theres and inverse relationship between the conductivity of a materail and how long it lasts. Many people think platinum and iridium are better conductors hence making them better. However, this is far from the truth. Copper is actually a FAR BETTER conductor that either of those two materials. Thats also why they have to be replaced every 30k as opposed to those worse conducting materials such as pltinum and iridium that will last 100k. Also, you have to remember that newer cars that recommend platinum plugs can do so because their ignition systems are far more advanced and are capable of supplying the increased voltage to make up for the lack of conductivity provided by copper. So, by putting plats or iridium or similar plugs in your old style ignition system, you are going to experience poor performance. IMO stick with copperplugs in your older vehicle and change them every 30k like youre supposed to.
Senior User
Joined: Dec 2009
Posts: 374
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From: Portsmouth, Va
Oh and the torque spec for my 300 is 15-20 ftlbs. If your spec is in inlbs, divide by 12 to get ftlbs
144 inch lbs is 12 ft lbs.
Posting Guru
Joined: Nov 2008
Posts: 1,183
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From: Pennsylvania Wilds
One thing to think about in regards to platinum, iridium, and copper plugs is theres and inverse relationship between the conductivity of a materail and how long it lasts. Many people think platinum and iridium are better conductors hence making them better. However, this is far from the truth. Copper is actually a FAR BETTER conductor that either of those two materials. Thats also why they have to be replaced every 30k as opposed to those worse conducting materials such as pltinum and iridium that will last 100k. Also, you have to remember that newer cars that recommend platinum plugs can do so because their ignition systems are far more advanced and are capable of supplying the increased voltage to make up for the lack of conductivity provided by copper. So, by putting plats or iridium or similar plugs in your old style ignition system, you are going to experience poor performance. IMO stick with copperplugs in your older vehicle and change them every 30k like youre supposed to.