I finally figured out why my truck was missing. The 3rd plug back IS fried. The electrode is gone plus about half of the ceramic. Since the Ford parts department is closed today. Could I get some NGKs or Densos at the Checkers or Napa? What part number could I use for the plugs. Only boost adder I have is a 2# upper. Thanks in advance.

 

Well, not many local places stock Densos, but if they do, IT20 is what you need. For the NGKs, you want the TR6, which is also known by stock number 4177. I think you'd have better luck finding the TR6s. Hope this helps.

 

I am not Sal, but I do know that Napa sells NGK spark plugs. I doubt you are gonna want TR-6's but the number for those is 4177. -Mat-

 

I ran the TR-6 for a little over a year with a 2# and had zero problems .

 

I thought you would just run a TR-5 but I guess that is why I am not a tuner. -Mat-

 

well it depends what he had in the truck to begin with. if all his other plugs are fine and they were the IT20s, then i would just pick one more of those up. if they were tr6s, then i would fine one more tr6.

*some* napa stores carry it20s but it's pretty rare...