what is wrong with closing the gap on 6510?

I only recommend the 6510, use them and they run good... while they last LOL these engines are so hard on plugs

 

Absolutely nothing just as long as you dont go ham on the whole gapping process. I just thought it was neat that there might be something else. (I am running the 6510s with no issue FYI). Yes these motors are hard on plugs. Mine opened up from .026 to .029 after my last national event in San Diego and I checked my gap back in April before going to the Pro Solo in Fontana.

 

I only go 10k on a set of plugs... to cheap to run them longer for as hard as I run them. I gap to .026 and I have never seen them open past .028 at 10k miles. Not saying it doesn't happen I know it does. and agree with you.

getting a proper tool and feeler gauges helps a lot. don't work the feeler gauges between the plug and diode. just use it for size reference. standard gapping tools are junk! and shouldn't be used on these plugs.

something like this
https://www.amazon.com/Torque-Solution-Precision-Spark-Threaded/dp/B073G7LCSL

 

I picked up a gapping tool similar to the one you posted and it has served me well and you are absolutely right about the feeler gauges. All too many times I've seen folks ruin plugs using those impulse item gap tools at the parts counter.

I may give these Motorcrafts a try since it appears they are about as easy to get as the 6510s

 

Doing some more research netted some more info on the SP542's. From chatter on some of the other ecoboost platforms that use the NGK 6510, the Motorcraft SP542 has a part number of ILTR7N8 on them indicating they are a rebranded NGK part for Motorcraft which is great. They are also 5.99 a piece at Oreily's, and 6.19 a piece through rock auto.

 

So I ordered a set of the Motorcraft SP542's through rockauto.com last week and got them in on Friday , but unfortunately they sent 3 out of the four

Right off the bat you can see that the gap is closer than what you would find on the NGK 6510's

Here is the incorrect SP578 on the left and the correct SP542 on the right

I did receive the correct SP542 through rockauto yesterday after I notified them last Friday of the fubar and they made good and shipped the correct part out quickly. *One interesting tidbit is that Ford supposedly replaced the SP542 with the SP578, however upon further research I found the SP578 is listed as a hotter plug.

If you do go to your local parts store, or dealership, DO NOT let the parts monkey tell you its the same thing as they are not. The SP542 is a one step colder plug and if you plug in the ILTR7N8 part number found on the SP542 plug itself into NGK's website , it confirms that it is a 1 step colder, and even more interesting is that it has almost the exact same specs as the NGK 6510.

SP542's

NGK 6510's

I will report back this weekend on how the SP542's compare to the NGK's

 

^Above^

Great work! interested to see your findings with these! also long term

 

I got a chance to install and test out the SP542s by doing a few pulls and so far they seem to match the NGK 6510s. I didn't capture any logs, but I was monitoring my SCTX4 on the pulls and did not see any odd ball corrections or knock. Overall they seem just like the NGKs except far easier to gap.

Here are the plug comparisons:

NGK (the oranging is from a previous tank of 91 and Torco)

SP542 (light orange from current fill up of 91 and VP Octanium Unleaded)

 

assuming they are re-brand 6510s with a tighter gap?

I guess whatever you can get for a cheaper price. I don't see any reason to buy the Ford plugs just because it has a tighter gap. you still have to gap them after all.

 

Just another option really. Not every setup fairs the same. Some cars do well with the 6510s while others do better with the itv22s and so on and so forth. At least this gives us another choice especially when these shi*tboxes are rough on plugs.

 

So aside from the Denso ITV22 and the NGK 6510, I appears that there is another option from Motorcraft in the SP-542 as a one step colder option that doesn't come with an as wide starting gap as the 6510's.

OEM one step colder plugs, 6510 alternative.

Has anyone tried these out on the FoST yet? Looks like Unleashed Tuning is selling them along side the NGK's as a 1 step colder alternative.

Sorry to revive this forum but No way motorcraft has step colder plugs!!! Are they iridium ?? Were they use for the ecooboost mustang?? This is defently a game changer cause ngk and other brands are not good for thus car it makes it to wide and breaks easy and runs rich

 

All spark plug manufacturers make spark plugs in most every combination of heat ranges and materials to fit most vehicles produced by all manufacturers; Motorcraft has been making these spark plugs for many years.