Spark Plugs - 93 and E85 on Tune

[goodlettjr]

I’m currently have roughly 40k miles on the clock. I’m set up with dual Palm Beach Dyno tunes. One for 93 and one for E85. My car spends most of its time on 93 for daily driving, but I plan on swapping to the E85 tune periodically for some weekend fun.

Since I'm at the 40k mark and switching to performance calibrations, I’m looking for some consensus on spark plug maintenance:

1. Preferred Plugs & Gap: For those running similar dual-fuel setups, what specific plug are you running? Are you sticking with the stock Motorcraft, NGK Iridium, etc..? Also, what gap is recommended for this setup?
2. Gap: Do you feel there is a "sweet spot" gap that works perfectly for both 93 and E85, or are you narrowing the gap specifically to prevent blowout on E85 at high revs?
3. Change Intervals: What are your realistic intervals for swapping plugs on a tuned S650? Ford says 100k, but I’m assuming that’s out the window now. Do you find E85 degrades the plugs faster?

Looking forward to hearing your setups and any "lessons learned.”

Thanks in advance!

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[robvas]

No reason to run anything other than stock plugs and stock gap

e85 won't wear your plugs out any faster

 

[cbrtrx]

I've found the best results at .045 for your application but you can leave them stock.

The factory motorcraft plug is an NGK iridium.

 

[Q6543]

It is so much extra work to do plugs on this car, I’d leave it alone.
You need to pull the battery, part of the rear cowl panel and remove the battery heat shield plate to get back into 7/8. Like a few hours.

 

[schmeky7]

If reduce your 3/8" tool drives to 1/4", have a 1/4" swivel, and some dexterity, you don't have to remove the battery or heat shield.

But it's still not easy.

 

[ZXMustang]

It is so much extra work to do plugs on this car, I’d leave it alone.
You need to pull the battery, part of the rear cowl panel and remove the battery heat shield plate to get back into 7/8. Like a few hours.

No you dont need to do any of that. I did mine a few days ago, took about an hour. A few socket extensions worked perfect. I removed my strut tower brace and the engine cover, and that was it. Getting to the back passenger side was the hardest, but if you use a 6" extension and a 5/8 magnetic deep well socket, you can feed it down. Then you can use another 3" and a ratchet and get it loose. Then remove the 3" extension and you can hand loosen it out and pull out the plug. Literally took like 10 minutes total on that back passenger side. The rest are all straight shot accessible with the 6 and 3 inch extensions. No wobble needed.

 

[Q6543]

I’ll need to add more tools, because i followed whipples instructions and had to do all that extra stuff.
Thanks!

 

[cbrtrx]

Yes I use 2 extensions like mentioned I can change all 8 plugs in 30 minutes.

 

[Wiley Marmot]

STOP it! You guys are bummin' me!

Looks like I'll be going for max mileage on my factory set of plugs!

 

[cbrtrx]

STOP it! You guys are bummin' me!

Looks like I'll be going for max mileage on my factory set of plugs!

Me personally I would definitely replace the plugs in your application since you're at 40k miles now.

 

[ZXMustang]

STOP it! You guys are bummin' me!

Looks like I'll be going for max mileage on my factory set of plugs!

It was super easy man. hour tops and that is swearing included.

 

[LouG]

A good quality 1/4 drive socket set can save you hours of misery. Also, surgeons forceps. Don't know how I did without them for so long.

 

[Wiley Marmot]

Me personally I would definitely replace the plugs in your application since you're at 40k miles now.

You must have misread my odometer. I've only got 9200 mi on my GT; hoping the plugs will make it to at least 10 K!

 

[cbrtrx]

You must have misread my odometer. I've only got 9200 mi on my GT; hoping bthe plugs will make it to at least 10 K!

I thought you were the original poster.

 

[goodlettjr]

I thought you were the original poster.

Lol. He wasn’t but I saw it.

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