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Discussion Starter #1
Hey all-

How long are the stock plugs good for? I've done the CAI/2.6 upper/tune. 17k miles.

How can you "tell" when they (plugs) need to be replaced?

Last time I replaced a set of plugs was on an old camaro with 400sb & headers - what a PITA! How hard is it to replace the plugs on the shelby? I'm not even sure if I have the right sockets!!

Any advantage of the aftermarket brand plugs & would changing to a different, non-stock set require a re-tune?

Do stock plugs come pre-gapped? (what is proper gap for stock ?)

Thanks!
TD
 

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If you have the 2.6 pulley and CAI/tune you really should be running an NGK TR-6 plug. Gap them at 0.032. They do not come pre-gapped. Plugs are very easy to change on this car. 30 minute job including a second beer......
 

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Wow Tricky Dick you got lots of questions for sure.
I will try to answer them as completely as I can.
Did you buy the car with the 2.6 pulley and tune? The plugs that you should have are the ngk6 the gap is 32 33 thousands. Never assume the gap has been set correctly from the factory. They get bounced around on trains and in trucks before the parts house get them always check them.
If you dont have the right plugs than you need to change them now.
I like to run my plugs for about 30,000 miles to make sure they are as fresh as possible and they are cheep. I have seen guys run them for years and decide to change them only to find them carboned up so bad they are hard to remove. When that happens usually the threads come with the plug. Need I say what happens next.
If you are not sure you have the tools to do this job you can buy the plugs and take them to the dealer and they will gap and change them for you. They will charge you but if anything goes wrong its on them.
If you go with the NGK6's you do not have to change the tune. you are good to go.
 

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Change plugs every 30-50K miles depending upon usage.

Always use anti seize on the threads for aluminum heads.

My stock plugs were fine until I was above 12lbs of boost. Just my $.02
 

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I believe the recommended service interval for the spark plugs is 100,000 miles; but don't wait that long. If you follow the recommended service interval you risk the plugs becoming one with the aluminum heads. I waited 99K to change them on my Honda Odyssey, however they did come off okay and were in all good shape. The OEM plugs are probably Platinum or Irridium.
 

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Discussion Starter #7
Thanks for the tips

So I got my TR6's and they came gapped higher than 0.032-0.033.

How do I adjust them down?

I bought a tool for checking the gap with the ramp around the ring of metal about the size of a $0.50 piece. Doesn't seem very accurate as the width of the spark plug electrode is about twice as wide as the hash marks. Is there a better way to check/set the gap on these?

I think I will use the anti-sieze, but it seems a controversial topic for sure. Poll?

TD
 

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You only want a VERY light amount of antiseize rolled into the threads ONLY. Not on the seat part, not below the threads on the electrode.

Nickel antiseize is best, due to the heat involved.

ONLY pull the plugs with the engine cold.

You will need an 8mm, 10mm, small torx bit (T20 or so), various extensions and a 3/8" ratchet.

Pull the coil covers and go to work. You'll have to pull the intake elbow and airbox lid on the driver's side and move a wiring harness on the pass. side just a little.

I'd suggest the NGK TR-6 plugs; or Motorcraft AGSF-12-FM-1; or Autolite AP103's. I'm running the AR103's (Autolite "race" plugs; with cut back over electrode...don't plan on getting all that much mileage out of them, but they run good :) ) I run the AR103's gapped at 40 right now, I'd drop to 35 or so if I was on higher boost (stock for now).

As far as closing the gap, a lot of times you can push hard with your thumb, or use a small piece of wood. Just gently push the electrode down, it's a "feel" thing, you'll get it.
 

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Thanks for the tips

So I got my TR6's and they came gapped higher than 0.032-0.033.

How do I adjust them down?

I bought a tool for checking the gap with the ramp around the ring of metal about the size of a $0.50 piece. Doesn't seem very accurate as the width of the spark plug electrode is about twice as wide as the hash marks. Is there a better way to check/set the gap on these?

I think I will use the anti-sieze, but it seems a controversial topic for sure. Poll?

TD
Lots of good advice already...yes, no matter what NGK recommends use anti-seize (light coating) and use a torque wrench.

You can buy a good gapping tool for about $15; ask for one that is a wire gapper...uses a u-shaped piece of wire for the various thicknesses and is much more accurate. They will generally also have a bending tool at the opposite end that has a little notch in it where you grab the electrode to bend it; there should be 4 or 5 notches for the different width electrodes. You can do it by pushing as suggested but it is hard to keep the bend uniform and you will end up with reduced contact area. You want the whole electrode the same distance from the anode for the entire contact area if possible.
 

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Discussion Starter #10
Thanks!

What is the torque spec?

8mm & 10mm sockets? Have a 10mm. I thought I'd only need a spark plug socket? Torx bits? I've got hand Torx drivers, will I need socket bits? Thanks for the advice all!

TD
 

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Make sure you use some electrical tape to fasten the spark plug socket and the extensions together. It's not fun to have to remove them from the deep plug well if they come apart.
 

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Thanks!

What is the torque spec?

8mm & 10mm sockets? Have a 10mm. I thought I'd only need a spark plug socket? Torx bits? I've got hand Torx drivers, will I need socket bits? Thanks for the advice all!

TD
Here are the specs...ignore the gap though with the NGK's and go with the 0.032" others have shared

http://iihs.net/fsm/?dir=217&viewfile=SPECIFICATIONS.pdf

Here are the instructions for removing the coils and spec for the coil cover bolt torque

http://iihs.net/fsm/?dir=220&viewfile=Ignition Coil-On-Plug.pdf

Here is for the plug re & re

http://iihs.net/fsm/?dir=220&viewfile=Spark Plugs.pdf

And finally the exploded view...this is easy as pie...just take your time and pay attention to details

http://iihs.net/fsm/?dir=220&viewfile=Engine Ignition Components - Exploded View.pdf

EDIT: for some reason this site doesn't accept links with a space in them....you can see they are all on the left pane when you get there....
 

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Discussion Starter #14
Thanks Again!

The parts store sold me some anti-sieze:

Counterman's choice - no info on what it contains.

Had to get some feeler gauges, the wire gap tool only went down to 0.040

Trying to reduce the gap is tricky, plus the cheap wire gapper that only goes to .040 puts little nicks into the soft outer electrode.....

There must be a better way...


TD
 

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I prefer a round-wire gapper...



You can roll it in/out safer and easier.
 

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The 8mm was for loosening the clamps on the stock air intake.

10mm deep for removing the hold down stud on the passenger side; rear coil-cover hold down.

Torx bits (or drivers) to remove the remaining coil cover bolts. T15 or 20; I forget, something about that size though.
 

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Make sure you use some electrical tape to fasten the spark plug socket and the extensions together. It's not fun to have to remove them from the deep plug well if they come apart.
Thats what magnets are for ;)
 

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Make sure you use some electrical tape to fasten the spark plug socket and the extensions together. It's not fun to have to remove them from the deep plug well if they come apart.
Harbor Freight carries a 5/8" spark plug socket that is 5" long. Makes it easier to extract the socket from the tunnel. I use it mainly to loosen and to tighten/torque the plugs. For extraction I like to use my Craftsman spark plug socket since it has a rubber insert that grips and holds the plug insulator. I use a length of 3/8" vacuum hose placed over the electrode to insert the plug and start the threading process to avoid the risk of cross-threading them.
 

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Discussion Starter #19
OK-

Bought a wire gap tool for the bender portion of it, but this is too thick to slip around the outer electrode because it hits the tip of the inner electrode. I tried bending from the curved part of the outer electrode, but it marks it up. It also rests on the insulator of the inner electrode and I think it might be possible to damage it. I am not sure the marks pose a problem, or not. I bought a set of feeler gauges that has a 0.032 blade. to check the gap.

I ordered another wire gap tool online through craftsman to pick up at the store - available in nearly 2 weeks! - only costs $2.12

This has from 0.25 up to 0.40 I believe - I am hoping the little bender part of the tool is smaller so I can grab the outer electrode without damaging the inner electrode tip.

So once I get the other tool I'll try gapping the rest of the plugs, one way or another.

Thanks for the tips on the sockets. I think I'll try the electrical tape trick.

As it turns out I have some torx bits lying around.

Thanks for the help.

TD
 

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OK-

Bought a wire gap tool for the bender portion of it, but this is too thick to slip around the outer electrode because it hits the tip of the inner electrode. I tried bending from the curved part of the outer electrode, but it marks it up. It also rests on the insulator of the inner electrode and I think it might be possible to damage it. I am not sure the marks pose a problem, or not. I bought a set of feeler gauges that has a 0.032 blade. to check the gap.

I ordered another wire gap tool online through craftsman to pick up at the store - available in nearly 2 weeks! - only costs $2.12

This has from 0.25 up to 0.40 I believe - I am hoping the little bender part of the tool is smaller so I can grab the outer electrode without damaging the inner electrode tip.

So once I get the other tool I'll try gapping the rest of the plugs, one way or another.

Thanks for the tips on the sockets. I think I'll try the electrical tape trick.

As it turns out I have some torx bits lying around.

Thanks for the help.

TD
Tricky Dick if you are having problems gapping and replacing plugs I would stick to your day job and let a mechanic handle the wrench. No offense taken please. Even VP Biden admits when its "Above His Pay Grade".:rofl:
 
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