GEN 2 Which plug should I go with Sp 550 or Sp578?

[Wender85]

I’m sorry if this has been posted in the past but I have looked up and down this thread and others. Im about to hit 20,000 miles and i want to change my plugs. My Raptor is stock other then an oil catch can, Borla ATK exhaust, and a drop in k&n filter. The reason why I thought about swapping them is because I have been hearing a very loud pop from time to time on deceleration coming out of my exhaust. As well as slight performance loss. I keep seeing different things about different types of plugs for our trucks and all I’m trying to do is purchase the best one for my truck with my set up. The sp578 are the direct replacement now but I can order the SP550. Please help me out I plan on doing this tomorrow afternoon thanx.

 

[Wender85]

Anyone?

 

[Badgertits]

SP542's are the colder plug many have gone to, if my memory is correct the stock plug part# for the Raptor may have changed but not this one? There was some confusion there....at any rate, most of the tuner/performance vendors advertising here sell em. I purchased from MPT - ask what they recommend. My truck is tuned, but even when stock swapping out around 10-12k miles I noticed less sputtering, noticeably smoother idle, smoother acceleration - again less "stuttering" or hesitation @ WOT. I think running 93 octane in sport mode + SP542s is as close to getting a "warrantied tune" as you'll get lol

 

[Wender85]

Can anyone give a link to where i can purchase SP 542’s

 

[Wender85]

Well nm o’ Riley carries them (SP 542)if anyone else was wondering. Thanx for the help

 

[Biggwrm]

Can anyone give a link to where i can purchase SP 542’s

ordered mine from here, amazon 43$ a set

Ford Racing M-12405-35t 10-c 3.5l Ecoboost Cold Spark Plug Set https://www.amazon.com/dp/B07HW1T57N/?tag=fordraptorforum-20

 

[Wender85]

Well o Riley doesn’t. Went to pick them up and it was the 578

 

[Biggwrm]

Well o Riley doesn’t. Went to pick them up and it was the 578

yea that was my experience, didn't want to jinx you. Figured maybe you were lucky at local spot. They don't show on website.

 

[Wender85]

Thank you for the link! I put them in my cart On Amazon. Ill let u know how rhey work out

 

[Biggwrm]

Is the consensus still 28 on the gap? Or 26.

I see ORA sells the same plugs pregapped for $89. But says .26 in title but .28 in description.