If you don't want to have to replace them after 15,000 miles you will want the iridium plugs or something designed to last 100,000 miles.
NGK has kick @$$ educational pages. Rock Auto has good prices on premium plugs. (I'm not affiliated with either, they've just been the best deal 4 me, I could care less what & where you buy
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Don't let ANYONE say "The plugs are pre-gapped, just put them in"
Total BS! Check the gap on whatever plug you buy to your cars specification!
NGK on Gapping Plugs
Since most modern engines are 99.5% efficient at burning the fuel in the cylinder, I don't think there's much yer gonna do to help that using a spark plug. Most claims are hype.
Prolly why this thread is in the Unicorn Corral
Look into Ford forums for advice as well, I know for my Honda there were plenty of opinions on spark plugs. I was able to sort of weed out the riff raff on them and came to the conclusion that 1 brand really was the safest bet for my Civic, so I went with that. You'll have to do your own search and come to your own conclusion on that.
Here's the Technical Overview of plugs from NGK, look at the FAQ's too for a goldmine of info.
NGK Spark Plug Technical Overview
These pages are very generic, they aren't hard selling or specing NGK at all, just straight dope on spark plugs from the peeps that make em.
