Just another vote for Autolite if Motorcraft isn't available. Just never a fan of Chumpion.

 

Growing up, my dad (a Caterpillar mechanic for many years until he retired) always had Ford service trucks and he told me to never run Champion plugs in a Ford. He said they just never worked right.

merhlin

 

one plug i've tried and didnt give a fair shake at was those e3's. I put them in a escort i had and after a few monthes i expereinced a goofy miss and it was all over the place. idle, cruise, under power and finally that cylinder just stopped producing power. i finally diagnosed it as a bad plug. it just quit working. called then a joke, swapped them out for autolites. looking back, should have just returned it and got another one. I gained 1 mpg with those plugs. a guy can get a bad plug from time to time. Also, had good luck with bosch platinum 4 plugs.

 

Please stay away from any gimmick spark plug. This includes anything like the following. E3 are just a made in China. The Bosch +4 are about the same. The same is true of SplitFire, if they are even still around. Electricity will take the path of least resistance.