Clarification on Upgrading Spark Plugs

[HangFire]

Originally Posted by Gebo
I'm not communicating properly. I'm talking about the affect on the electronics prior to the spark plug. I'm not asking about performance or anything mechanical within the engine.

I'm talking about any component before the actual spark plug itself.

Even as far as affecting the wires, could and even computer long term.

Basic attributes of a spark plug (ignoring multiple electrodes for a moment) are: thermal conductivity (heat range), gap, and resistance. Resistance includes the resistor core and the conductivity of the electrodes. (Of course the air gap is resistant as well). Practically speaking, if copper core conventional plugs are fresh, the electrode resistance is close enough and doesn't matter. It is only when they are old and carbonized that it begins to matter, but at that point they should be replaced.

My take on it, on the topic of sensitive engine electronics versus spark plugs, assuming you don't swap in non-resistor for resistor plugs, it all has to do with the gap. Iridium and Platinum plugs typically come with, and are spec'ed for, a large gap that works well with modern high energy ignitions. Putting in a tighter gapped copper/nickle plug might burn out modern electronics due to increased amperage.

Likewise putting a larger gapped Iridium or Platinum plug in an older system would make for a weak spark, and would exhibit the symptoms of a plug with excessive wear (which is to say, excessive gap). The increased long-term conductivity of the precious metal tips is not going to make up for a larger air gap.

There are complications. For example Rock Auto has a graphic they slap in most Spark Plug info screens showing Iridium as always superior to Double Platinum. But this does not match all manufacturer's product positioning. Also product positioning and marketing can be confused as well.

For example NGK's Iridium IX (a very good plug used as OEM by my Honda) is a single Iridium electrode and is sold at a lower price than the Laser Platinum which has both center electrode and tip a precious metal. NGK markets the Laser Platinum as the "OEM Style" and the Iridium IX as "Performance" but the Iridium IX is the actual OEM plug for my Honda Pilot. I put in Iridium IX's 106K miles ago and they worked fine. My mechanic put in Laser Platinum's last week when he did the timing belt and valve adjustment... after two tanks of gas... they work fine, too. Exact same fuel economy as the last 2 tanks on the old 105K+ mile Iridium IX plugs.

Other complications are switching brands, which increases the possibility of resistor core resistance and thermal range changes. Multiple tip plugs that are not OEM specified. Manufacturers changing OEM plugs during an engine lifespan, with or without ignition changes. Differing user experiences with available plugs All enough to fuel the forum wars whenever a new reader asks "what's the best plug for my XXX YYY?"

 

[doitmyself]

Here's what NGK emailed back to me today when I asked if there was any data to support the idea that it is o.k. (or not) to use platinum or irridium plugs in a FCA vehicle that came from the factory with standard copper core/nickel electrode plugs:
"Hello,

Thank you for your E-mail. I do not have any data for you, but the reason I believe they used nickel spark plugs up to 2013 is they wanted to keep cost down. After enough customer complaining on service life, in 2014 they switched to an iridium spark plug. NGK has the iridium version listed as an upgrade for the OE nickel for pre-2014 models. An iridium spark plug will always be more efficient in flame propagation than a nickel spark plug.

Regards, Michael Durocher, Technical and Training Specialist , NGK Spark Plugs (USA), Inc."

 

[Cressida]

Quote

An iridium spark plug will always be more efficient in flame propagation than a nickel spark plug.
]

I would have thought it would have depended on the spark itself so I wish he would have mentioned why ?

Is there some difference in flame structure, burning velocity, flame stability or quenching ?

 

[DrDanger]

The OP wants to know the effects on his ignition system.
They are good. Less voltage/current is needed to produce a spark on your iridium. Why - less inductance. Why - less metal.
Why - less electrode to be ramped up to 20-50 000 Volts (Denso's iridium electrode is 6x smaller than standard copper 2.5mm). Yep up to 50 000 not the 120 / 240V powering your home.
Your ignition coils need to step up 12-14v to that amount there. With reduced voltage you have reduced current (all else equal)
and less interference to cause issues with you car computer or anything else electrical. You may not notice much, but iridium is better, been using it for 5-6 years and wont go back.

 

[benjy]

iridium will be more efficient lining our pockets because we make more profit is the reality!! if not for the fact that spark plugs are a part ot the longer emissions warranty in newer cars they would all have the cheap basic plugs IMO. i f your a DIYer + plugs are easy use the basic ones, but if paying labor $100 hourly + or - depending whos doing the work + where you live longer lasting plugs make dollars + sense, as do tough time consuming installations!!

 

[DrDanger]

The thinner electrode on the Iridiums gives a better spark , according to Denso.
https://www.denso.com/global/en/pro...parts-and-accessories/plug/iridiumpower/

 

[kschachn]

Originally Posted by benjy
iridium will be more efficient lining our pockets because we make more profit is the reality!! if not for the fact that spark plugs are a part ot the longer emissions warranty in newer cars they would all have the cheap basic plugs IMO. i f your a DIYer + plugs are easy use the basic ones, but if paying labor $100 hourly + or - depending whos doing the work + where you live longer lasting plugs make dollars + sense, as do tough time consuming installations!!

Let's take my old Honda Accord as an example. Conventional, cheap Denso plugs are about $2.50 each and iridium plugs are about $8.85. The conventional ones have to be changed out at about 30,000 miles and the iridium ones at around 100,000. So how is that lining Denso's pockets?

I do all my own work so my labor is free, but even then why do I want to do the job 3 times when I can do it once for an equivalent price?

And FWIW, yes I do leave them in that long. And the ones I've removed at 100,000 miles (in all my vehicles below) have shown signs of wear but they look pretty good. They might even last longer than 100,000 miles.

 

[HangFire]

Originally Posted by benjy
iridium will be more efficient lining our pockets because we make more profit is the reality!!


Better profit for me.

NGK heavily promotes their Iridium IX line over their Laser (Double) Platinum line... and they cost less!

At AdvanceAuto, for my '05 Pilot, the OEM NGK Iridium IX are $7.99/ea, NGK V-Power's are $2.59/ea, NGK Laser Platinums are $14.39/ea. OEM is Iridium IX.

At 30K versus 105K replacements, the V-Power's would cost me $0.000518/mile, while the Iridium IX only $0.000456/mile.

 

[DGXR]

IMO it is best to stick with the factory-spec parts. Doesn't have to be OEM parts, but the spec should be met. You can change to a hotter plug to combat issues such as fouling. Or you can change to a colder plug if you have added boost engine. Many people have switched from standard to iridium/platinum plugs without issue, but the ignition system may be stressed due to the parts (resistance, etc) not being factory spec. This might not cause an ignition failure now, or ever, but it certainly could.

 

[Kawiguy454]

Lots of good comments. The only real reason to opt for the boutique plugs is longevity so you don't have to change as often to keep the car running well. A lightning bolt of 50,000-80,000 volts could give a rats behind about what metal is in the electrode tip. the materials in plugs is all about how well they hold up to the recurring violent plasma event they function in. And a few ohms resistance +/- in the plug or wire is for completely different reasons.

 

[demarpaint]

Originally Posted by kschachn
Originally Posted by benjy
iridium will be more efficient lining our pockets because we make more profit is the reality!! if not for the fact that spark plugs are a part ot the longer emissions warranty in newer cars they would all have the cheap basic plugs IMO. i f your a DIYer + plugs are easy use the basic ones, but if paying labor $100 hourly + or - depending whos doing the work + where you live longer lasting plugs make dollars + sense, as do tough time consuming installations!!

Let's take my old Honda Accord as an example. Conventional, cheap Denso plugs are about $2.50 each and iridium plugs are about $8.85. The conventional ones have to be changed out at about 30,000 miles and the iridium ones at around 100,000. So how is that lining Denso's pockets?

I do all my own work so my labor is free, but even then why do I want to do the job 3 times when I can do it once for an equivalent price?

And FWIW, yes I do leave them in that long. And the ones I've removed at 100,000 miles (in all my vehicles below) have shown signs of wear but they look pretty good. They might even last longer than 100,000 miles.

That is the same logic I applied to replacing the OE copper plugs with upgraded plugs in my Liberty. I do my own work too, and I have better things I can be doing than swapping plugs.

 

[nthach]

If the car came with copper, it can be safely upgraded to a OEM-style(NOT the original Bosch enclosed tip design) Pt/Ir plug with no problems. I'd done that in a Subie and a Mitsu that took a standard copper plug and it might be better for waste-spark ignition. Otherwise stick to the OEM plug type.

Now some cars should only stick to the OEM plug - Saabs and older Audis called for a certain Bosch plug. But there are problem children out there like Ford's 3V mod motors.

 

[Skippy722]

I put autolite double platinums in my 5.7 hemi that had copper plugs. Was told all sorts of horror stories and how I'm an idiot for changing from the GOD TIER COPPER PLUGS!!!! It ran great when I traded it in. 20,000 miles ago, I did the same to my Caliber, except it got NGK Iridium plugs. Same stories, same results. Runs great.

Plugs like E3 or those pulstar plugs are gimmicky. If your car came with a standard single electrode plugs, use that. But I'll always recommend upgraded plugs for newer cars over standard copper plugs unless it's a beater.

 

[Rhymingmechanic]

Originally Posted by Gebo

My understanding is the electronics set up is different for different types of spark plugs. And that my car will work better if I don't switch from Platinum to Iridium as the ignition system was set up for Platinum plugs.


My 2001 Silverado came with NGK Laser Platinum plugs, gapped at .060. A few years later, GM put out a bulletin that changed the recommendation to iridium plugs gapped at .040.

I ran regular NGKs in a cooler heat range for a while (trying to eliminate a ping) and then switched to the iridiums with no ignition problems so far.

 

[CR94]

Originally Posted by Snagglefoot
... Using copper plugs? Might as well get out the buggy whip.
Unless you enjoy changing plugs so much that you're doing it 3 to 6 times more often. ...
Humbug! I used "copper" plugs over 100k miles multiple times without problems.

 

[Skippy722]

Originally Posted by CR94
Originally Posted by Snagglefoot
... Using copper plugs? Might as well get out the buggy whip.
Unless you enjoy changing plugs so much that you're doing it 3 to 6 times more often. ...
Humbug! I used "copper" plugs over 100k miles multiple times without problems.


You can also run your tires down to slicks, doesn't make it right. My Caliber has 60k on the copper plugs and they were toast.

 

[CR94]

Originally Posted by Skippy722
Originally Posted by CR94
Originally Posted by Snagglefoot
... Using copper plugs? Might as well get out the buggy whip.
Unless you enjoy changing plugs so much that you're doing it 3 to 6 times more often. ...
Humbug! I used "copper" plugs over 100k miles multiple times without problems.
You can also run your tires down to slicks, doesn't make it right. My Caliber has 60k on the copper plugs and they were toast.
Not an apt analogy. When you replace tires that you've "run down to slicks," they'll function much better, especially as to wet traction. When I replaced the 100k+ plugs, the engine did not function differently. That was NOT in a Caliber.

 

[Skippy722]

Originally Posted by CR94
Originally Posted by Skippy722
Originally Posted by CR94
Originally Posted by Snagglefoot
... Using copper plugs? Might as well get out the buggy whip.
Unless you enjoy changing plugs so much that you're doing it 3 to 6 times more often. ...
Humbug! I used "copper" plugs over 100k miles multiple times without problems.
You can also run your tires down to slicks, doesn't make it right. My Caliber has 60k on the copper plugs and they were toast.
Not an apt analogy. When you replace tires that you've "run down to slicks," they'll function much better, especially as to wet traction. When I replaced the 100k+ plugs, the engine did not function differently. That was NOT in a Caliber.


An average guy living in say... Las Vegas or any other dry, relatively warm year round area, would at best hardly notice the difference between worn out tires and a brand new set.

 

[bobdoo]

I will replace my current plugs, when needed, with the double thin-electrode plugs. I'm doing this because I had clear evidence of easier, quicker starting after clipping the ground electrodes shorter, exposing more fresh charge to the spark, on a whole bunch of cycles and snowmobiles.

They also allowed a highly-tuned yamaha to rev higher with more power. It had crappy coils at the time. I strapped on two full-size auto coils, which fixed that particular problem.

 

[SteveSRT8]

A great example is my 06 sig car. The 5.7 Hemis were all copper cores, nickel electrode. The 6.1, with EXACTLY the same coils and hardware came stock with the NGK hybrids. So that is one example of a ride that will run the same either way.

An expert tuner I know who specializes in Mustangs feels the higher end plugs take boost better. I think what he means is that they give more spark intensity at the gap with the same current.

I have read about ignitions that are multi-strike and actually use the impedance across the plug gap to read the conditions in the chamber and fire again multiple times in a single combustion event.

My Polaris jet ski is a totally solid state sealed ignition. One time the dealer switched the plugs and it never ran right until we switched it back to OEM.

So it varies wildly by mfgr and platform...