Spark Plug questions

[REDSHOCGO]

I think the ones he got were sp528

[REDSHOCGO]

What is the difference between the sp528 and sp534 spark plugs my cousin Said these were the ones recommended for my vehicle when he pulled up the info at ford

[DJE624]

528 are platinum, 534 are iridium.  And, I think according to one chart I saw, the tips are different (that may be the materials).

[REDSHOCGO]

Hmm I wonder if there will be a difference in performance because I didn't use the sp534s.

[DJE624]

I doubt there is any noticeable difference.  If you gapped them at 30 you should be fine.  I had 528's. I think they upgraded the material for the '13 to iridium.

[SwampRat]

I got my NGK  Iridium ix  LTRR71X-11 stock # 6510 in the mail today .
I plan on putting them in tomorrow evening after I pick up my SHO from the body shop in the Morning.
Any one know if there is any " special " type of gaping tool to use on iridium plugs ?
I've never used iridium plugs before and get the impression the electrode is somewhat easy to damage .
Can I just use a standard feeler gage and gap them at .030  ?

[Night Hawk]

This is what i use

[futat2]

This is what i use

That will work, just don't try to gap by forcing the .30 gage part of it between the electrode and collector. Use the cut out part to bend the collector in waterer direction it needs to go.

[bykr]

Hmm I wonder if there will be a difference in performance because I didn't use the sp534s.

No,there's no hp in plugs,just getting the right heat range.

[Needmoreboost]

The proper plugs gapped correctly can help prevent spark blowout at higher (tuned) boost levels.  So in that case it would help performance. 

[Joleat]

I just replaced the plugs in my stock MKS earlier today. The car has just a tad under 50k miles. The coloration was good. Four of the six plugs were right at .040" and the other two were slightly above at around .042"-.043". I replaced them with Motorcraft SP534s gapped at .030". The car runs smooth, but I wasn't have any problems with the old plugs. I just wanted to see how they looked at around 50k miles.

[DJE624]

Thanks for the pics.  They don't look too bad for 50K.  With those old gaps, you should feel a little smoother running up top now.

[BiGMaC]

The proper plugs gapped correctly can help prevent spark blowout at higher (tuned) boost levels.  So in that case it would help performance. 

Right on!
They also prevent preignition and detonation as timing advances in a tuned ride especially.  Very important with our 11:1 compression.

[MeanKS]

I plan on getting the SP534 plugs.  should they be gapped at .28 or .30?

i also noticed that the recommended maintainence on the MKS says 'spark plugs' at 37,500 miles.  does that mean Ford recommends to replace the plugs at 37.5K?  seems kind of early for that.

also, where did you guys buy your plugs?  seems like most places are selling them about $4-$6 dollars a piece...

[Brucelinc]

I plan on getting the SP534 plugs.  should they be gapped at .28 or .30?

i also noticed that the recommended maintainence on the MKS says 'spark plugs' at 37,500 miles.  does that mean Ford recommends to replace the plugs at 37.5K?  seems kind of early for that.

also, where did you guys buy your plugs?  seems like most places are selling them about $4-$6 dollars a piece...

O'Reilly auto parts has them for 3.99 if you have a store locally.  I personally would not go under .030.  Mine came gapped at that.  Where are you seeing a recommendation of changing plugs at 37,500?  Is that under the severe service recommendations?