New Motorcraft plugs would have given the same result over the worn plugs that you replaced.

 

You'll have to forgive some of us who suspect that the difference you felt was due to the old plugs not working very well, rather than the new plugs you chose being superior to other new plugs.

 

Your seat of the pants dyno isn't going to be very accurate. If you are expecting to feel a difference, you will. In medical terms it's known as the placebo effect.

 

I just looked at the e3 on Advanced website. That's another weird looking contraption. What is it supposed to do that others (Splitfire and others) won't? This looks like a $56 + $400 for the cop's. Shoulda bought the 72 suburban!

 

The coils only need changed if they fail, so no big expense there. The correct plugs cost about $32 so that's cheaper than cap, rotor, wires etc.

 

How can you tell if the coil is good or bad? Is there a tester somewhere out there?

 

copper core plugs are the best for N2O and forced induction because it produces a "hotter" spark since it is a better conductor of electricity.

I only use Autolites or Motorcraft plugs in my Fords.

 

Glen, A Haynes manual should give the specs to check them with an ohm meter. That's how I found a bad coil pack on my Windstar. 5 of the 6 fired great, one was dead. I do not know the ohm specs on the COP's. I have seen many have corroded springs inside the boot, which caused a bad contact to the plug.

 

haha, whether there was sarcasm in that statement or not, i took no offense.
im in highschool, and was blessed with this 3 and a half ton 5.4 (no sarcasm intended), but i obvioulsy dont have much money. i love the truck to death, and have big plans for it, but i cant pay for driving around getting 11 mpg all day. i heard some good things from a friend, so i decided to give them a try.
my previous plugs had been replaced 7000 miles ago, so naturally they were clean. i felt the power increase right away. previously, i would get about 320-330 miles to the tank, but my last 3 fills ive made i drove 345, 350, 345...so i did see a little, in both mpg and power

you dont need to believe me, but i did see a little

 

I have my Haynes Manual (#36060 on the binding) in front of me - it doesn't show a ohm reading. I'm pretty sure that I wouldn't know how to use the old analog electrical tester to read the ohms anyway. My wife might.

Could I pull a few coils and see what they might be measuring to use as a baseline?

 

Yes, they all should be pretty close to the same.

 

By the way for anyone wishing to know - the coils that I pulled all measured around 5 ohms - with 2 measuring about 4 ohms. I didn't get to the back passenger side. I found 2 boots on the drivers side that were wet and rusty. One even blew a rock out as I was blowing them out.

I did have Motorcraft dual platinum plugs and I replaced them with Autolight dual platinum. I'm sure there isn't any difference.

 

You need to measure the secondary resistance also.

 

(showing my electrical ignorance): What is secondary resistance? How is it measured?

 

Resistance from the plug terminal to the primary side.