When in doubt, the best replacement is typically OEM. That means Motorcraft. In the case of the 302, there are a lot of aftermarket parts. I'm currently running Motorcraft in my 302. But I'm one of those kinds of guys that will put in something else, if I can save a buck. I just bought some E3 spark plugs for my 256 (4.2L V6). Has anyone tried those?
put in what the book says dont go by anything else, Fords use motorcraft or autolite plugs. The e3 plugs say they shoot the spark directly into the mixture, uh dont all spark plugs do that. Dont waste your money, they dont improve anything. Just like the bosch plugs are junk in anything except foreign cars. Well this is my 2 cents anyways.
Uh, No they don't all do that! W/ the E3's, I've never used em (probably never will) but have heard pleasant thing's about em. They do project better than a standard designed, stock gap plug & they are Copper cores! I'd say if your running a stock gap (they're pre gapped & must stay that way) give em a shot & tell us what you think.
Yesterday I obtained Autolite sparkies for my truck; I think the Accel ones are misfiring. Next week I gonna change them. The truck rides nice, but while on the accelerator there are some misfires.