Would you use Iridium Plugs in a Ford 4.6 DOHC?

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My Lincoln Mark VIII is about to turn 88K miles and has 12 years on the original plugs. It still runs well, but I'm going to replace them soon. I was considering the NGK Platinums or Iridiums. Are iridiums okay in these Ford engines? Thanks in advance.
 
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Minneapolis
echoing bdcardinal, waste of money, use the factory recommended Ford plug and it will easily go 75k before needing replacement. I tried the iridiums in a 94 Crown Vic and noticed hard starting in the winter, I think the iridium plugs are a little cold for the engine design
 
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Iridium plugs have a finer longer lasting tip. They were $7 each at AAP. Not sure if NGKs work well in Fords. I know Motorcraft and Autolite plugs are NOT recommended in Toyotas or any Japanese cars.
 
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I have NGK TR55GP G-Power platinum plugs in my Crown Vic. The car runs great with them. If you don't mind changing the plugs every 5 years or so, then there's nothing wrong with the platinum plugs.
 
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MS
Mod motors do really well with NGKs, I ran them for years without issue. But they also do well with Motorcraft and Autolites, these days I use nothing but Motorcrafts (coppers in the Mustang, platinums in the DD).
 
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 Originally Posted By: panthermike
My Lincoln Mark VIII is about to turn 88K miles and has 12 years on the original plugs. It still runs well, but I'm going to replace them soon. I was considering the NGK Platinums or Iridiums. Are iridiums okay in these Ford engines? Thanks in advance.
Nice timing on your post. I've got a '93 Mark VIII 4.6 DOHC that I will be buying plugs for and installing this weekend. I will probably go with Autolite or Motorcraft plats. My mind is still open, however.
 
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 Originally Posted By: hate2work
I'd find out what kind of plugs are in there now that gave you 88k and put the same ones back in.
+1 I am sure they are Motorcraft so I would definitley stick to that..A friend of mine has a 97 Mark 8 and has 90K miles on original Motorcraft plugs and they are doing just fine..He said when they come out Motorcraft is going right back in.
 

panthermike

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 Originally Posted By: hate2work
I'd find out what kind of plugs are in there now that gave you 88k and put the same ones back in.
That would be Motorcraft Platinums! Looks like I got my answer, thanks everyone.
 
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Copper motorcraft or autolite plugs for the best performance (but not longevity).. Use what the manufacturer recommends for longevity (probably platinum). Copper conducts better than platinum, iridium, or any other metal.
 
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 Originally Posted By: JustinH
Copper motorcraft or autolite plugs for the best performance (but not longevity).. Use what the manufacturer recommends for longevity (probably platinum). Copper conducts better than platinum, iridium, or any other metal.
Copper does not conduct better than silver.
 

panthermike

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I went from Autolite Platinums to Autolite Coppers in my 94' Mark VIII and there was no performance difference. I'll definately stick with the platinums.
 
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 Originally Posted By: chevrofreak
 Originally Posted By: JustinH
Copper motorcraft or autolite plugs for the best performance (but not longevity).. Use what the manufacturer recommends for longevity (probably platinum). Copper conducts better than platinum, iridium, or any other metal.
Copper does not conduct better than silver.
Thanks, I didn't know of any silver spark plugs..
 
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 Originally Posted By: JustinH
 Originally Posted By: chevrofreak
 Originally Posted By: JustinH
Copper motorcraft or autolite plugs for the best performance (but not longevity).. Use what the manufacturer recommends for longevity (probably platinum). Copper conducts better than platinum, iridium, or any other metal.
Copper does not conduct better than silver.
Thanks, I didn't know of any silver spark plugs..
You said any other metal, you didn't specify only metals that were used in sparkplugs ;\)
 
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