autolite or motorcraft are your best bet, i have never got good performance with anyspark plug other than autolite and motorcraft. like others have stated, these are the best. choose wisely. motorcraft is the stock with motorcraft wires. the crappiest spark plugs you can buy are the boschs and the splitfires, they arent made for the american cars, they are only good for the european cars. i had a set in my 93 5 liter and they sucked compared to the motorcraft. also, the guy who owned my 300zx b4 me put them in, they sucked there also. only the old style of one electrode and arm are the best. i had splitfires in my bike, the splits fouled and i replced them with the old style, and the bike has never performed as well. motorcraft and autolite only here.