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Evo 9 Spark Plugs

So i just found out the Evo 9 spark plugs are different then the evo 8 plugs.. with that being said i would like Copper plugs but i cant find a site that sells them?

if they dont sell them i guess ill go with the stock plugs ILFR7H.. while they are Iridium can you gap them? i think stock they are gapped .024-.026? i wanna to gap then .020

copper alternative, cross refereanced with nissan 350z plugs.

PLFR6A-11 (3672)

have mine gapped down to .21

Quote:

Originally Posted by 4g63evoeight (Post 9676732)

copper alternative, cross refereanced with nissan 350z plugs.

PLFR6A-11 (3672)

have mine gapped down to .21

Wrong. Those are the wrong heat range.

OP- get the stock ones and drop them in. There is no copper alternative to the evo 9 plugs. I wouldnt try to gap the iridiums because you are going to scrape off the iridium coating.

If you're purchasing the stock IX spark plugs, they may not need to be gapped, however... if they need to be gapped, I would certainly do it.

The iridium is on the pin (center electrode) of the plug. The ground electrode (which is the hook part) isn't irridium, nor does it have (at least that I've found) any precious metal in it. So when setting the gap in an iridium plug, you should be using a feeler gauge (not one of those silly coin gauges), and be sure you're using it correctly. By that I mean, not scraping or applying pressure to the iridium tip. Only adjust the ground electrode.

You can find more info on NGK's website.

I'll reference this specifically though.

Quote:

Q: Do I need to set the "gap" when installing a new set of plugs?

A: Maybe. A spark plug part number might fit hundreds of different engines from many different manufacturers. Although the NGK factory will set the gap to a pre-selected setting, this may not be the right gap for your particular engine. The incorrect plug gap for your engine can contribute to a high rate of misfires, loss of power, plug fouling, poor fuel economy, and accelerated plug wear. It is always best to check the gap against the manufacturer's specifications. If adjusting the gap on fine wire or precious metal plugs such as platinum or iridium be very careful not to apply any pressure or prying force to the fine wire center electrode or insulator as they can be damaged. The gap should be adjusted by only moving the ground electrode.

Another consideration that should be taken into account is the extent of any modifications that you may have made to the engine. As an example, when you raise compression or add forced induction (a turbo system, nitrous or supercharger kit) you must reduce the gap (about .004" for every 50 hp you add). However, when you add a high power ignition system (such as those offered by MSD, Crane, Nology) you can open the gap from .002-.005".

If you have any questions, please contact the NGK Sparkplugs Tech Staff:
Tech Support - Click here

The manufacturer of your vehicle, the company that produced the aftermarket products you've used and/or your mechanic are all additional sources of gapping information if you've modified your vehicle.

Quote:

Originally Posted by turbotalawd (Post 9678810)

OK. gapped down they work PERFECT for me, buschur sells them too.. im pretty sure we went over this before.

say what you want, i'll do what i want and i KNOW they work. for you to say otherwise is ridiculous.

Quote:

Originally Posted by 4g63evoeight (Post 9681780)

I dont really care who sells them. Fact is fact: they are one heat range hotter than stock plugs = wrong plug.

Quote:

Originally Posted by ProPilot04 (Post 9678903)

Just wanted to note that you can, in fact, use "one of those silly coin gauges". If you use them correctly, they work just fine. You are supposed to use the hole in them to increase the gap... It is unfortunate, however, how lazy people can be by just trying to "slide" the gauge around to the correct size... In that case you would be correct; all it does is grind down the electrode, not increase the gap...

Yes, but a feeler gauge is still going to be more accurate...

When I got new plugs they were almost perfectly gapped at .020

Bringing this thread back from the dead so I don't have to make a new one.

Can someone tell me the proper gap I should have on my IX, I'm running 25psi. I'm getting them regapped tomorrow

I set mine to .021" in accordance with the owners manual (.020-.023).

I saw this in another thread, "YUP! The gap is usually going to be dictated by how much boost you're running and your particular turbo set up. On stock Evo's running somwhere between 17-20 PSI I believe the gap is .028-.031; 20-25 PSI = .025-.028; 25-30 PSI = .022-.025; 30+ PSI =.018-.022.
(Disclamer)
Now getting away from the what works on the VIII vs. IX argument, these are just plug gap settings that I have seen numerous Evo owners use on their cars by virtue of the boost levels they were running and by no means am I attempting to tell you this is what will 4 sure work on your set up. This is just my .02 "

but thats for an evo 8 and from my understanding the gap from the 8s is different from the 9s. Hope someone can chime in!

Quote:

Originally Posted by jason42003 (Post 11186717)

I set mine to .021" in accordance with the owners manual (.020-.023).

Are you running more boost like 25lbs? What is it stock? thanks for your quick reply!

I run 21 lbs boost. Which even by the table you posted is tight for the 25 lbs you run. I believe pretty heavily in running the stock gaps on my stock setup. It's a good starting point and if you feel like you need more gap than you can always open it in .001 increments until you experience break-up. But I have never had an issue with that gap and I don't feel like fixing something that isn't broke haha.

but the table I found was stated for evo 8s so I was wondering if there was a similar table for the 9s

run the biggest gap you can,