Read my plugs ?

Gabe

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I changed the spark plugs in my wife's '08 Shelby a couple days ago, NGK TR6's that have been in for about 7-10k miles.
The gaps were all over the place (started at .030 when installed about 1.5-2 yrs ago), and 2 of them look light in color.
Car has 67k miles on it, has had a '13 TVS pushing about 17 psi for about 1.5-2 years, put down 656/661 on a Dynojet, and it runs great.
Please let me know what you think.

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Close-ups of each individual plug:

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redfirepearlgt

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I'm interested to hear more about this. I hope someone with a trained eye will chime in and give some detail.

Great macro photography btw. Love the detail.
 

pass1over

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i'm no expert, but from the reading i've done and my experiences .... 2, 4 and 6 look a tad lean, the rest look good. The slightly tan insulator is what your looking for.

I agree, great pics, super detail. There's a mark that you wanna be able to see on the grounding strap as well. From what I can see in the first couple of pics, it's in the right spot, timing is good.
 

46addict

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I am no expert either, but from my days of checking plugs on two different 3v engines and bone stock 2vs, mine look like your #2. Did these plugs have any idle/part throttle time on them prior to pulling? I've read the engine needs to be shut down after a WOT run (i.e. at the big end of a dragstrip, coasting the car to a stop with the engine off) to get a good plug reading.
 

pass1over

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Did these plugs have any idle/part throttle time on them prior to pulling? I've read the engine needs to be shut down after a WOT run (i.e. at the big end of a dragstrip, coasting the car to a stop with the engine off) to get a good plug reading.


Was going to go back and add this, got interrupted when I was posting originally. Yea, need to shut off the car at the top of a WOT run with no idle time (if possible) to get a plug reading. Idle is a lot leaner than a WOT pull, so it'll change the reading on the plugs.
 

stkjock

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FWIW - From my limited understanding of reading plugs:

1) You want plugs that have a single pass/pull to read them properly for any value.
2) you need to cut the threads off to really see what's up

like this:

leanandmean.jpg
 

Gabe

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These plugs have no 1/4-mile passes on them.
They're out of my wife's Shelby, the car has been over 110 only once with these plugs in it, when it saw 140-145 mph as it was leaving a Lamborghini Gallardo behind, lol.

Other than that, it's normal driving, which is to say, somewhat aggressive, sometimes more so.
 

redfirepearlgt

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These plugs have no 1/4-mile passes on them.
They're out of my wife's Shelby, the car has been over 110 only once with these plugs in it, when it saw 140-145 mph as it was leaving a Lamborghini Gallardo behind, lol.

Other than that, it's normal driving, which is to say, somewhat aggressive, sometimes more so.

Your wife gapped a Eurotrash Lambo in a Mustang? I love it!

"You're killing me Smalls" - Sandlot
 

Gabe

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Your wife gapped a Eurotrash Lambo in a Mustang? I love it!

"You're killing me Smalls" - Sandlot

Lol, well, it was her Mustang, but her son was driving, he's raced all kinds of things and honestly, between the three of us, he'd be the best to do that.

The wife, well, she picks on every damn Corvette she comes upon. She's got a radar for those things, can smell them before she sees them, and the hunt is on!
 

redfirepearlgt

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Lol, well, it was her Mustang, but her son was driving, he's raced all kinds of things and honestly, between the three of us, he'd be the best to do that.

The wife, well, she picks on every damn Corvette she comes upon. She's got a radar for those things, can smell them before she sees them, and the hunt is on!

I like how your wife thinks. I am the same way if I roll up on one. Guilty as charged. Not making her HP (or yours) but I haven't had a vette pull on me yet....plenty out there that can, I am sure though. No shame in losing to a Corvette with my simple little GT automatic with just the one bolt on power adder.
 

travelers

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I am no expert either, but from my days of checking plugs on two different 3v engines and bone stock 2vs, mine look like your #2. Did these plugs have any idle/part throttle time on them prior to pulling? I've read the engine needs to be shut down after a WOT run (i.e. at the big end of a dragstrip, coasting the car to a stop with the engine off) to get a good plug reading.

Was going to go back and add this, got interrupted when I was posting originally. Yea, need to shut off the car at the top of a WOT run with no idle time (if possible) to get a plug reading. Idle is a lot leaner than a WOT pull, so it'll change the reading on the plugs.

FWIW - From my limited understanding of reading plugs:



1) You want plugs that have a single pass/pull to read them properly for any value.
2) you need to cut the threads off to really see what's up

like this:

leanandmean.jpg

You have to do that WOT shutdown on a fresh set of plugs to get a true reading. We use a plug scope to look down into the bottom of the plug.

Gabe do the stock plugs from Ford have the split electrode? I think the stock plugs are the iridium tipped if they are like the GTs. I would think with the split electrode the spark could jump to the ground from either side of the electrode. Not a very good flame pattern. If you just put fresh plugs in, I would swap some injectors around and see if the lean plugs follow the injectors. But before that I would put the old plugs back in and run some injector cleaner through the system. My fingers aren't working very good tonight.

This is what we use on the race car plugs.
https://www.summitracing.com/parts/pow-pow301080
 

Gabe

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Injectors were replaced at the same time as the plugs.
We put on the TVS, new plugs, new OEM '13-'14 GT500 injectors, all at the same time, about 1.5-2 years ago. The blower then came off a couple months later to have a friend shave off the "5.8" off the blower and to paint it. That took a couple months, no rush since it was winter anyway.
Not sure about the factory plug design. When she bought the car it had NGK TR6'S in it already
 

stkjock

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You have to do that WOT shutdown on a fresh set of plugs to get a true reading. We use a plug scope to look down into the bottom of the plug.

That was my point
 

Gabe

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Have you reached out to your tuner with this info and pics?

No, but a friend of mine that's built countless engines and helped install the TVS on the wife's Shelby looked at them and says they look fine.
Car drives fine, no fluid losses, no drivability issues.
Gonna run the new TR6 plugs I just put in for the rest of this season and probably switch to the NGK TR7IX, a one-step-colder plug and an iridium plug at the same time, so they should last longer and be a better overall plug for this application.
 

86GT351

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No, but a friend of mine that's built countless engines and helped install the TVS on the wife's Shelby looked at them and says they look fine.
Car drives fine, no fluid losses, no drivability issues.
Gonna run the new TR6 plugs I just put in for the rest of this season and probably switch to the NGK TR7IX, a one-step-colder plug and an iridium plug at the same time, so they should last longer and be a better overall plug for this application.

That works. Just make sure the gaps are a little more consistent
 

o2sys

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Gabe what are those tiny specks on them? You can clearly see it especially on plug #5. Is that metal particles from detonation?

Mine from forged 3v has it too and afraid it might from detonation:
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RocketcarX

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They are fine, slight oil contamination, thats the ashiness on the electrode base. Otherwise they look textbook.
Add a PCV catch can.
 

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