TR6 Plug Issue

[xfrosty63x]

I had issues with rough idling with the TR6 plugs gapped at 0.032, but the car also had an issue with a high idle due to a vacuum leak I finally found after swapping throttle bodies for the second time. The TR6 has been a great plug when it comes down to power, and I have zero issues with them in my Lightning.

I wanted to see if I could get my idle under control, so I installed the TR6IX with the gap out of the box like many people have used, and my idle is now as smooth as I could ever hope for. But I soon found that I had a spot of hesitation at low RPMs, and the car also had issues with power under load. So I pulled them out tonight and regapped them to 0.032. I found that they were gapped slightly above 0.035 which is where my feeler gauge stops. The car still seems to idle great, but I haven't had a chance to take it out and may not get a chance until tomorrow.

I hope this solves my hesitation problems, or the TR6 are getting put back in.

 

[Blk4V00GT]

After reading this thread a couple weeks ago I decided to go with the tr6ix with my 2.8 upper swap I'm doing. Should have the car done In a couple weeks to see how they do.

 

[mr.magic]

yo Blk you got any updates? I gots a problem and i praying it's plugs but they looked ok. Pulling them again and checking with a mag glass right now.

 

[gamebred26]

i see alot of tr6 but on lower hp cars...what about 20 psi of boost over 600 whp etc guys?

 

[Blk04Snake]

How are you all saying that TR6 is 2 heat ranges colder than stock? I just looked up on NGK's website and it lists the following for 04 Cobra:

V-Power TR6
G-Power TR6GP
OE Laser Iridium ITR6F13^
Iridium IX TR6IX

So what's the deal?

 

[Bdubbs]

How are you all saying that TR6 is 2 heat ranges colder than stock? I just looked up on NGK's website and it lists the following for 04 Cobra:

V-Power TR6
G-Power TR6GP
OE Laser Iridium ITR6F13^
Iridium IX TR6IX

So what's the deal?

Who's saying it's two heat ranges colder? It's only one heat range colder than stock. The TR7 is two heat ranges colder. What you listed above is the type of plug. The tr6 is a copper plug and the tr6ix is iridium.

 

[Blk04Snake]

Who's saying it's two heat ranges colder? It's only one heat range colder than stock. The TR7 is two heat ranges colder. What you listed above is the type of plug. The tr6 is a copper plug and the tr6ix is iridium.

What I listed above is what NGK lists for stock replacement. Not any heat ranges colder or hotter

 

[earico]

Heat ranges are like treadwear ratings on tires. They are only consistent within the same manufacturer. See this straight from NGK:

The heat range numbers used by spark plug manufacturers are not universal, by that we mean, a 10 heat range in Champion is not the same as a 10 heat range in NGK nor the same in Autolite. Some manufacturers numbering systems are opposite the other, for domestic manufacturers (Champion, Autolite, Splitfire), the higher the number, the hotter the plug. For Japanese manufacturers (NGK, Denso), the higher the number, the colder the plug.

If NGK lists the TR6 as a OEM replacement then I would tend to believe that it is the same heat range as stock.

 

[Bdubbs]

What I listed above is what NGK lists for stock replacement. Not any heat ranges colder or hotter

NGK's stock replacement is TR55 v-power plug. Not quite sure where your looking? Or maybe there website is messed up? Ask any tuner that know's these car's and they would straight up say the tr6's are 1 heat range colder. If it was stock heat range just imagine how many pullied cobras, lightnings, and shelbys would be having problems!

NGK TR55 V-Power Spark Plugs (Set of 8) [TR55] : Lethal Performance, Performance parts for Ford Mustangs

And here lethal list's it as 1 heat range colder.

http://www.lethalperformance.com/96.../ngk-tr6-v-power-spark-plugs-set-of-8-p-18295

 

[t56speed]

Installed my tr6's yesterday made a few pulls. No issues at all
I.gapped them at .035

 

[Blk04Snake]

NGK's stock replacement is TR55 v-power plug. Not quite sure where your looking? Or maybe there website is messed up? Ask any tuner that know's these car's and they would straight up say the tr6's are 1 heat range colder. If it was stock heat range just imagine how many pullied cobras, lightnings, and shelbys would be having problems!

NGK TR55 V-Power Spark Plugs (Set of 8) [TR55] : Lethal Performance, Performance parts for Ford Mustangs

And here lethal list's it as 1 heat range colder.

NGK TR6 V-Power Spark Plugs (Set of 8) [TR6] : Lethal Performance, Performance parts for Ford Mustangs

NGK's official website is where I'm looking. TR55 is not listed anywhere. Here's a screenshot of the application:

 

[Bdubbs]

NGK's official website is where I'm looking. TR55 is not listed anywhere. Here's a screenshot of the application:

Interesting, I wonder what they would say if you called them and asked? That's the only site I've seen where they listed them as oem replacements. Not sure if one heat range colder would be bad or not on stock boost? I do know that if all us pullied cars were running the stock heat range there would be tons of detonation going on!

 

[earico]

Interesting, I wonder what they would say if you called them and asked? That's the only site I've seen where they listed them as oem replacements. Not sure if one heat range colder would be bad or not on stock boost? I do know that if all us pullied cars were running the stock heat range there would be tons of detonation going on!

Call them and get a tech on the line and see what they say. Just remember that heatrange numbers between Ford & NGK aren't necessarily direct comparisons.

 

[1wild-horse]

read here:
Sparkplugs.com - Spark Plug 411
some good info. majority of problems @ idle is gap gap gap gap gap gap! Gap wisely gentlemen

 

[ray77]

so im doing plugs on a stock cobra and a cobra with a 2.8 upper and exhaust tommorow. i thought i knew which one i was gonna use but these thread has me lost now.

so are the tr6 not the way to go? does the cobra with the pulley need something colder? its getting a dyno run sunday so i'd like it to be setup clean for it.

so tr6?XP103's?

 

[MalcolmV8]

Just use the TR6. It's a heat range colder and a good copper plug that works very well for most of us. I've been using them for 6+ years with no issues at all. Some have idle issues and apparently some hesitation on low rpm throttle. If you end up been one of those then get the expensive Iridiums. I don't see the point in getting them unless you have an issue with the copper. No re-tune is required for changing plugs.

 

[mooch91]

Interesting, I wonder what they would say if you called them and asked? That's the only site I've seen where they listed them as oem replacements. Not sure if one heat range colder would be bad or not on stock boost? I do know that if all us pullied cars were running the stock heat range there would be tons of detonation going on!

I think heat ranges changed throughout the production of the Cobra, no? In which case "stock" is relative to the date of manufacture.

 

[04screamingvert]

Since the gap size has a direct affect on the spark plug's tip temperature
and on the voltage necessary to ionize (light) the air/fuel mixture, careful attention is required. While it is a popular misconception that plugs are pre-gapped from the factory, the fact remains that the gap must be adjusted for the vehicle that the spark plug is intended for. Those with modified engines must remember that a modified engine with higher compression or forced induction will typically require a smaller gap settings (to ensure ignitability
in these denser air/fuel mixtures). As a rule, the more power you are making, the smaller the gap you will need.

A spark plug's voltage requirement is directly proportionate to the gap size. The larger the gap, the more voltage is needed to bridge the gap. Most experienced tuners know that opening gaps up to present a larger spark to the air/fuel mixture maximizes burn efficiency. It is for this reason that most racers add high power ignition systems. The added power allows them to open the gap yet still provide a strong spark.

With this mind, many think the larger the gap the better. In fact, some aftermarket ignition systems boast that their systems can tolerate gaps that are extreme. Be wary of such claims. In most cases, the largest gap you can run may still be smaller than you think. I got this info from the NKG web site. I also have this trouble at 1500 t0 2200 with the TR6 gap at .032 from the tuner. I checked my stock plugs tonight and they were gap at .045 all 8. I will try a regap of the TR6 before I buy the Iridium IX.

 

[ray77]

Just use the TR6. It's a heat range colder and a good copper plug that works very well for most of us. I've been using them for 6+ years with no issues at all. Some have idle issues and apparently some hesitation on low rpm throttle. If you end up been one of those then get the expensive Iridiums. I don't see the point in getting them unless you have an issue with the copper. No re-tune is required for changing plugs.

i understand a tune is not needed, its getting a tune anyway weather i change the plugs or not. I'm going to change the plugs out before is all.

 

[MR.SCOOPINATOR]

I was running the tr6 in my set up had a bad popping sound at idle and bad stupder at 1200 to 2200 rpms. Talk to my budding whos a svt mechanic. He said go back to the motorcraft stock plug , gab it at 50 and see what happens. Changed the plugs today. my car runs better then it ever did with thoses tr6s. I read alot of poeple saying after they have done the pully change that they have had the same prob. Ive been chasing this prob for three months. Seems my car likes the stocker plugs better. Mods on my car are 276 pully change kn filter . She runs like a stipped ass ape going after pussy now. Just my two cents on thoses tr6 plugs. When all eles fails go back to the stockers. Best of luck every one....