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Discussion Starter · #1 ·
and although they're still stock heat range, you should still install & tune with them. that is all.

NGK #3672
Model LFR6A-11

gap to .028" ftw
 

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bought some a couple weeks ago to try out. The nice thing about these is, you can go to autozone and they may have them in stock or if not they'll have them at 7:00 AM the next morning.

Still haven't gotten around to installing though.
 

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Discussion Starter · #5 ·
Flycaster said:
Please explain why everyone should do this.
because i'm not much a big fan of platinum/iridium spark plugs, they're great for longevity but that tiny tip does nothing but hold heat, copper doesn't last as long but it's the best conductor and IMO does a better job at getting heat out of the combustion chamber than these platties/irids you never have to change
 

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I understand your point, but I've never heard of anyone recommending their use outside of single event race motors (especially those using NOS). I think they're the wrong plug for any street car - you'll be changing them much more often since they have a tendancy to foul more easily and the tip breaks down much faster. I know where you're coming from, but I think if plug generated detonation is a concern, that is better delt with via a colder range plug.

Just my opinion.
 

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Discussion Starter · #7 ·
Flycaster said:
I understand your point, but I've never heard of anyone recommending their use outside of single event race motors (especially those using NOS). I think they're the wrong plug for any street car - you'll be changing them much more often since they have a tendancy to foul more easily and the tip breaks down much faster. I know where you're coming from, but I think if plug generated detonation is a concern, that is better delt with via a colder range plug.

Just my opinion.
I also tried the step colder NGK iridiums and really I like these best, but I also don't have a problem changing my plugs every 10k miles and the machine is tuned, fouling isn't a concern
 

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overdose said:
...I also don't have a problem changing my plugs every 10k miles and the machine is tuned, fouling isn't a concern
Gotcha. It'll be interesting to see how they do in the winter - most of us out here are tuned as well, but the cold weather (I'm talking zero) is an issue. Let us know what you think after you've had 'em in for a while.

Frankly, I'm thinking about either turning off my injection or going to warmer plugs this winter. My car takes forfreekingever to get up to normal temps in the middle of winter; it runs more than a little "rough" for a long time, and the use of high-boost maps and injection on snow and ice is kinda silly anyway. There's no point in trying to put 400whp to the ground when 150whp is already too much. :lol:
 

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overdose said:
because i'm not much a big fan of platinum/iridium spark plugs, they're great for longevity but that tiny tip does nothing but hold heat, copper doesn't last as long but it's the best conductor and IMO does a better job at getting heat out of the combustion chamber than these platties/irids you never have to change
The plug electrode material isn't what gets heat out, its the ceramic insulator that does that not the electrode.
Iriduim tips are much better in forced induction motors because, even though it doesn't have the conductivity of copper, the miniscule tip requires less spark energy to fire. And as you (should) know, as cylinder pressure goes up it takes more energy to fire the plug, and so iriduim plugs are significantly less likely to misfire than a copper plug.

This is where the claims, and dyno proof, for iridium plugs "gaining" horsepower come from. It isn't that the plug is really causing a gain, it is just firing properly where copper/platinum plugs were misfiring.

Now, if you have enough spark energy to fire copper plugs (and most coil on plug systems do) then iridiums won't gain anything or be any better (or worse) than copper, except for the iridiums still last longer and are more resistant to fouling and oxidation.
 

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Discussion Starter · #12 ·
gohrsepwr said:
dont know if thats a good idea for stock set up.
why? it's the stock heat range... I had LFR7AIX one step colder ngk iridiums in for a few months, tried these the other day and am more pleased with them....
 

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gohrsepwr said:
i read somewhere in here by a tuner that the copper plugs are better for more agressive tuned and boosted engines.
found it: http://www.projectwrx.com/caringforyourvehicle.pdf go down to 6-2
And there is dyno evidence of iridiums gaining horsepower (due to misfires), and it is nearly always on boosted motors:
http://www.europeancarweb.com/projectcars/0401ec_mini_cooper_s_engine_tuning/

http://www.importtuner.com/tech/0406it_projektz_power_upgrade/photo_05.html
http://www.importtuner.com/tech/0406it_projektz_power_upgrade/index.html


600 HP lost with coppers and platiums:
http://www.advanceautoparts.com/english/youcan/html/pht/pht20010101ds.html

Wish I could find the full test that (I think) import tuner did a few years ago that had all thier dyno charts. On their N/A VTEC motor the iridiums didn't change anything. But on their boosted integra they saw 6-9HP gains across the top end with the iridiums.

My 944 turbo misfires like no tomorrow on coppers, iridiums take care of the problem.
But, it is like I said before, it is only when their is a problem with your existing ignition system that iridiums make any difference. But I'll still take the longevity of them over coppers.
 
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