OK Boys and girls I'm going to throw this out here and see who has any real world feedback for me.

It is sparkplug changing time. I am contemplating the virtues of going up to a high performance plug. i.e. Splitfire, Bosch Platinum + etc.

So my questions are who has any experience with an aftermarket so called hihg performance plug.

I am a bit familiar with the Splitfire in a conventional electronic ignition. But the newer HEI ignitions will pretty much put a spark through a nail if it needs to. I see them burn the electrode down to a tiny nub and they keep sparking. So that being said, who has used/seen/recommended a high performance sparkplug.

I can read all the hype and gaurantees in the world. Means nothing to me. I want to hear from actual use. They all say theirs is the best thing since internal combustion. But in reality the ignition systems are pretty darn good these days.

Do they improve A) performance B) mileage C) chmaber cleanleness. O.K. C) is going to be an optional answer as I doubt anyone has had to actually prove that one yet.

I am going to cross post this in Engines as well as other aftermarket if I can figure out how to do that?....

 

I ended up going with the Autolite Platinum Pro simply because it's exactly like our Motorcraft Platinum plugs but goes one better and has a platinum disc welded to the outer electrode so the spark is firing between two platinum electrodes.... and therefore the gap of the plugs shouldn't increase over their lifetime.

Regular plugs always grow in gap as the outer electrode wears away slowly.

I haven't heard any glowing reviews about the Bosch Platinum +4's (4 electrodes between the spark and the combustion chamber.... ok... whatever). Tried Splitfire's once in my Ranger. Wasn't impressed.

The theory of split spark, etc is all BS anyway. The spark is going to take the path of least resistance which will generally be the same one every time.

It's such a pain in the a$$ to change them that I was looking for something to offer at least OEM performance and outlast OEM.

Don't re-use your Ford wires either, they're junk.

Like you said... with 40kv+ output on these ignitions you can pretty much use a nail or a nub and it'll spark.

 

I have a 4.2L auto, w/3.08:1 gears.
My window sticker:
https://www.f150online.com/galleries...9-74-21309.jpg


Because Ford makes 7 engines for our trucks with a seemingly endless number of computer programs, you really need to either stick with the OEM parts or experiment till you find what works for your truck. There really isn't a magic formula.

There is the:
4.2L V6 Gas
4.6L V8 Windsor
4.6L V8 Romeo
4.6L V8 Natural Gas
5.4L V8 Gas
5.4L V8 w/supercharger
5.4L V8 Natural Gas

Each of these engines responds differently to certain spark plugs.

I have a '97 4.2L with computer program VPV2. I was averaging around 15mpg in my everyday driving of about 20% city 80% metro highway driving when I decided to change plugs. At 56,000 miles I changed my plugs to Bosch +4's along with FMS 9mm wires and also started using Mobile 1. My milage went up to an average of 19mpg in the exact same driving situation. I've also had milage as high as 25mpg on 90 octane at 55mph on a day long drive around Southern Minnesota.

At 70,000 miles, I found that the FMS wires were offering such a varied resitance that some my plugs were fouled. I replaced the wires with OEM Motorcraft and tried different plugs. Motorcraft plugs gave me the same bad gas milage as did the Autolite platinum's. Champion Truck plugs seemed to provide more power but the gas milage was even worse. I'm now using Bosch Platinum plugs and OEM wires with 87 octane and averaging 18mpg on a very smooth running engine.

My goal is better gas milage, not performance.

A plug change on the V6 is easy compared to the V8's. Everything is accessible so it only takes about 20 minutes.