Which NGK spark plugs should I buy? [Archive] (2024)

HoustonMiata

22nd April 2009, 12:23

Hello everyone,

I'm thinking of replacing the spark plugs and wires on my 91. I went to Moss and noticed they offer the following:

-NGK Copper 1600 plugs Part #971-050 @ $1.95 ea.
-NGK Iridium plugs Part #971-086 @ $7.95 es.

Which one should I buy and what benefits can I expect from the Iridium plugs vs the copper ones?

I installed the Iridium plugs in my old 99 and didn't really see any performance improvement so I'm thinking I may just get the cheap ones this time.

As always, thank you for your feedback! :wave:

Ken

mattsedona

22nd April 2009, 12:32

Sprout97

22nd April 2009, 23:32

wallijonn

23rd April 2009, 00:07

what benefits can I expect from the Iridium plugs vs the copper ones?

That all depends.... As you go through the gears all the way to red line do you detect a "dead spot" above 5000 RPM? (as if there's no more torque, as if it feels as if it is "petering out," as if it's cruising.) If not, then get the copper plugs. Even if you do, you'd have to install the copper plugs and see if the problem goes away. You should have new plug wires to test and re-test, and you may need to re-time it if it is too advanced or too retarded; and test again and again. If you can tell, it may be that you also need a new O2 sensor.

If you can't tell, if you don't know what your timing is set at, or if you seldom rev all the way up to red line, save yourself the bucks and get the copper plugs.

Yes, I can tell the difference between the copper plugs and the Iridium plugs. Hell, I can tell the difference between NGK Iridiums and Denso Iridiums. On my car. I'll be switching back to the NGK Iridiums when the Denso plugs finally wear out.

ArchHoagland

23rd April 2009, 00:41

Just replaced mine a few days ago on my 1991 Miata.
Went to Mazda and got what they recommended for my 1.6 engine.

NGK BKR6E-11. $3.96 with the 20% discount I get for being a member of the local Miata club.

Runs a bit better now according to my wife. Those were what were in it but they were pretty far gone. Bought the car used and have about 102,000 miles on it. Don't know when those plugs were put in.

I pretty much stick to OEM parts for my cars. I used to buy the "upgraded superduper make your car faster" stuff and found out it was mostly snake oil.

smustang1234

23rd April 2009, 00:44

Just replaced mine a few days ago on my 1991 Miata.
Went to Mazda and got what they recommended for my 1.6 engine.

NGK BKR6E-11. $3.96 with the 20% discount I get for being a member of the local Miata club.

Runs a bit better now according to my wife. Those were what were in it but they were pretty far gone. Bought the car used and have about 102,000 miles on it. Don't know when those plugs were put in.

I pretty much stick to OEM parts for my cars. I used to buy the "upgraded superduper make your car faster" stuff and found out it was mostly snake oil. +1

NAman

26th April 2009, 20:33

Consensus is the copper are just as good as any other option, just change them every 25-30 K and you will be fine. Many replace the wires with NGK blues at that interval also.

I totally agree. I changed both the plugs & wires on my '95 after buying it a few months ago, and it runs like a champ w. copper NGKs & blue wires.

John151

26th April 2009, 21:12

LonewolfXb

26th April 2009, 21:17

RI ZoomZoom

26th April 2009, 21:32

+1 on the cheap NGK plugs.

Just put these in my car. The old ones the PO put in were the same exact plug!

rkjjeep

26th April 2009, 21:49

gtxhawaii

26th April 2009, 22:33

NAman

27th April 2009, 12:41

NAman FLY NAVY, old airdale here '63-'67.

You're about 10 yrs. before my time. Flying w. CAP these days, low & slow (except in the Miata!) ;)

David Edwards

27th April 2009, 15:23

I would go to AutoZone and get the Champion plugs for $1.79 and the Duralast wires (lifetime warranty) for $30.99.

They work just as good, indistinguishable from the more expensive brands.

Spend the money you'll save on something fun, or send it to me if you wish : )

Dan

27th April 2009, 15:27

Autolites? Champions and Duralast??

NGK ONLY! *very* distinguishable from the others on quality, heat range and are *not* expensive.

David Edwards

27th April 2009, 23:33

Dan,

Not to start an argument, but please can anybody and I mean anybody show me any OBJECTIVE evidence that NGK Blue wires make ANY MEASURABLE DIFFERENCE in anything?

HP?

MPG?

TORQUE?

The only thing they do is make your wallet $10 lighter than AutoZone wires, and in 2-3 years when you have to replace them yet again another $40 lighter, since the NGK wires do not have lifetime warranty.

John151

28th April 2009, 00:09

Dan,

Not to start an argument, but please can anybody and I mean anybody show me any OBJECTIVE evidence that NGK Blue wires make ANY MEASURABLE DIFFERENCE in anything?

HP?

MPG?

TORQUE?

The only thing they do is make your wallet $10 lighter than AutoZone wires, and in 2-3 years when you have to replace them yet again another $40 lighter, since the NGK wires do not have lifetime warranty.

I am a firm believer that the best plug wires can do is work properly. No shades of grey - they either work properly, or they have issues. However, after reading many posts, I got the impression that the NGK boots fit better, resulting in a reduce risk of having issues. So, for me, the $10 was more for peace of mind than for HP.

Sprout97

28th April 2009, 05:42

Ignition wires don't add power. That said, bad wire or poorly constructed wires will reduce power. As for more supporting information, there's a wonderful FAQ section at Magnecor:

http://www.magnecor.com/

Also, there's a nice -- but dated (1996) -- book on ignition systems (including wires), The Doctor's Step-By-Step Guide to Optimizing Your Ignition , by C. Jacobs, PHD,EE.

While it's merely ancedotal on my part, my car "seems" brighter in the response department since I swapped out my NGK Blues (along with the plugs)(15K on both) with Magnecor 8.5mm wires. Previous plugs were still good. Haven't refilled the tank yet, so I have no idea if there's mpg gain. Granted, 8.5mm wires on a stock engine is overkill, but then, I haven't ruled out some tweaking under the hood down the road :rolleyes:

Dan

28th April 2009, 08:47

Dan,

Not to start an argument, but please can anybody and I mean anybody show me any OBJECTIVE evidence that NGK Blue wires make ANY MEASURABLE DIFFERENCE in anything?

HP?

MPG?

TORQUE?

The only thing they do is make your wallet $10 lighter than AutoZone wires, and in 2-3 years when you have to replace them yet again another $40 lighter, since the NGK wires do not have lifetime warranty.

I've never mentioned HP/MPG or TORQUE, it's about reliability and the material used. NGKs fit better than other aftermarkets and they last longer because of better insulating material.

I see a number of cars come in with Autozone wires or equivalent and they arc like crazy because of their lack of insulation and the end result is usually a damaged coil and/or burnt plugs. Just going by experience here.

d

David Edwards

28th April 2009, 15:32

Again, where's the OBJECTIVE evidence.

Has anybody done a statistically valid test to prove they last longer? I doubt it.

And if NGK Blues are the end all be all, why do so many of them have to be replaced every few years too?

I have nothing against NGK Wires, but this seems like one of those myths that gets passed down over the years with no empirical evidence to support it.

Skullduggery

28th April 2009, 15:39

I am running "AutoZone" wires and have NO, I repeat NO issues. The work fine, and if they don't take 'em back and get brand spanking new ones, no questions asked!

I have been using them for years on many cars and have never had a set just "go bad"...

That is my 2 cents on the issue... But hey, if you have the money to waste on something that can't be verified, knock yourself out... I will use the extra cash for those things I want, or when it really does matter to buy OEM or the like.

David Edwards

28th April 2009, 15:49

Dan

28th April 2009, 16:02

Again, where's the OBJECTIVE evidence.

Has anybody done a statistically valid test to prove they last longer? I doubt it.

And if NGK Blues are the end all be all, why do so many of them have to be replaced every few years too?

I have nothing against NGK Wires, but this seems like one of those myths that gets passed down over the years with no empirical evidence to support it.

Next time I have sparks flying out of the bottom of the wires, i'll be sure to snap a picture and send them to you.

d

wallijonn

28th April 2009, 18:38

While it's merely anecdotal on my part, my car "seems" brighter in the response department since I swapped out my NGK Blues (along with the plugs)(15K on both) with Magnecor 8.5mm wires. ... I have no idea if there's mpg gain. Granted, 8.5mm wires on a stock engine is overkill...

What my mechanic friend says is that the 8.5mm wires will completely dump the coil current due to the larger wire core (about 2.5mm), which should help in emissions. The resistance of the Magnacores are supposedly 2.2K ohms / ft., the NGK blues are supposedly 2700 ohms/ft. Most regular spark plug wires are about 5000 ohms/ft. What I am deeply interested in are the new NGK Racing Power Cables, p/n 01z-6054 which are supposedly 270 ohms/ft. or 900 ohms/meter. Those babies should be able to dump most of the current right into the plug and give a better fuel burn (better emissions). But at about $100 I think I can wait.