SP542 Thread

[Guy]

I’m not.

I’m pretty shocked. I was a total skeptic. I thought.... placebo effect...

And... nope...

I just wish someone could tell me why a “colder” plug would make the truck run that much better... I’ve NEVER experienced this kind of performance change with a spark plug change. EVER.

In my mind... going to a colder plug is for the purposes of limiting preignition and knock, particularly in a boosted application.

I need my man from Livernois to weigh in why this works!

you have GOT to be ******* ******** me

 

[10SpdsOfFury]

It was day and night on mine when I switched from NGK to 542’s. As soon as I started it the truck was smoother and quieter. It’s the strangest thing that a plug can do that but it’s true and I wonder why Ford put them in the 2.7 but not 3.5.

 

[Guy]

I’d like to know if there is more to this than just a colder heat range.

Is there something different about the plug? Different resistance? Different spark geometry based on the strap design?

I just don’t get why one heat range colder will make this kind of difference.

Where is Fordza 1? Maybe you know. It’s a chance to wow me.

It was day and night on mine when I switched from NGK to 542’s. As soon as I started it the truck was smoother and quieter. It’s the strangest thing that a plug can do that but it’s true and I wonder why Ford put them in the 2.7 but not 3.5.

 

[Micha]

Colder plugs with a tight gap also help you when you and if you choose to go E85.

 

[kpg81]

If you need SP542's I ordered via Amazon and they came super quick.

https://www.amazon.com/gp/product/B00OAKP3B2/ref=as_li_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=B00OAKP3B2&linkCode=as2&tag=koast-20&linkId=83aeca7650d9a44a1fe35411b5b1cb05

 

[Guy]

Me too

They are very easy to change too.

I followed the torque specs from Ford.
133 inch pounds which is 11.1 foot lbs if you roll that way.

Watch snugging up the bolts for the coil packs too. They are a low torque spec as well.

Stock plugs are still a .030 at 15,000 miles and were burning a BEAUTIFUL chocolate.

So the plugs were fine. This effect is from
The plugs themselves.

If you need SP542's I ordered via Amazon and they came super quick.

https://www.amazon.com/gp/product/B00OAKP3B2/ref=as_li_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=B00OAKP3B2&linkCode=as2&tag=koast-20&linkId=83aeca7650d9a44a1fe35411b5b1cb05

 

[Ckhris]

you have GOT to be ******* ******** me

LOL
My thiughts exactly

 

[VSTOLG4]

My torque wrench is in storage. Do you think a good tight snug is good enough? I've been working on cars a long time and have never torqued a spark plug to specs. I just didn't know there was such a thing.

Yeah I get it...$75,000 truck without a $25 torque wrench in his toolbox.

 

[Guy]

This is the first time I ever torqued Plugs too.

Why? I figured I might as well. I can tell you based on the torque wrench they aren’t as tight as if normally crank them.

My torque wrench is in storage. Do you think a good tight snug is good enough? I've been working on cars a long time and have never torqued a spark plug to specs. I just didn't know there was such a thing.

 

[Ditchplains1]

xrocket21,

My best friends father when I was growing up used to talk about how much better the car would run after changing plugs, points, oil, filters. My father too could tell the difference; I have changed the oil/plugs/filters hundreds of times and never could tell any difference. But Mr. Jackowski and my Dad always could tell...

Eddie