Any one uses the NGK Iridium plugs and can Recommend the Proper Gap?

Manual says .031 min. The plugs themselves when measure are at .038
A SL Member recommended .042 on an old post.

What would you say is the Life / Interval change of these plugs vs Stock?

TIA

The LUV MOBILE is Coming!

MR LUV

__________________

 

NKG's site recomends a .32 for the iridium plugs in our engines. # BKR5EIX
http://www.ngksparkplugs.com/part_fi...engineid=37362

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.

 

Try using the plugs that come with from the factory. The copper plugs will give you more voltage, all Iridium does is last three times longer. Also, gap the plugs a little tighter than what they recommend, as its going to get bigger all on its own in time. If you dont care about changing them more often, the NGK copper U plugs are really the way to go.

 

I don't recommend you gap the iridium plugs. The "tip" is way to fragile. For the most part, Iridium plugs should come pre-gapped. There are some cases that you can shorten the gap but trying to widen it will either end up a success or you'll end up with a plug that you can't use.

fyi. the electrode on the iridium plugs is .4mm compare to factory iridium electrode/platinum tip ground, .7mm. which is why I don't recommend gapping them.

question is, did you get the factory iridium/platinum tipped plugs or the real iridium plugs?

 

IMHO, NGK plugs should be gapped to NGK specs.

They come "big" so that you can gently "tap" them down smaller. If you go too far and need to open them up, NEVER pry on the outer electrode with pliers or a screwdriver to do so! There are tools (looks like a super small spanner wrench) to gently bend the outer electrode open. Care must be taken to not pry or lever against the fragile .4mm (point four mm) electrode or ceramic.

Three times the life span for the iridium sounds good to me! Slower wear means it will stay in the ideal gap zone longer.

Ignition voltage is directly related to the ignition system. Not sure how any type of plug will increase that.

 

NO - spark voltage it proportional to the spark plug gap because the coil will generate an increasing voltage to the plug until it jumps the gap or arcs inside the coil or insulation of the plug. The smaller electrode of the Iridium plug produces a more concentrated e-field and lets it spark easier and at a slightly lower voltage than a bigger electrode with the same gap. The Iridium is a tougher metal and will last longer and allows the tip to be a finer point without burning up from the spark energy. They are supposed to produce a better projection of the spark energy to better ignite the A/F mixture. I am waiting for my NGK Iridium plugs to arrive this week. If you gap the plug too big they will misfire under heavy load and probably damage the coils.

 

I purchased them as an Aftermarket item from the local Napa auto store.
Set of 4 in the box; NGK Iridium IX - BKR5EIX

No gapping instructions on the box. My manual says .031min.
I measured .038 out of the box, I did Search and found an old post
from 2 years ago where the poster recommeded gap to .042
I have not pulled the Original plugs yet and wanted to get some info first.

My Box just turned 45,000 miles and runs like a champ.

What type are the Original plugs?
When do you suppose to change them?

TIA,
Next year, The LUV MOBILE is Coming!

MR LUV

 

You shouldn't have to change the oem plugs until 100-120K miles, but that imo is pushing it.

OEM plugs are the Iridium with Platinum ground. the Iridium IX is just a plain Iridium plug which is better then OEM Iridium Platinum.

You can adjust the gap like said above; You would just have to be carefully about adjusting them.

 

I was under the impression that a coil will produce a certain amount of voltage. For example, 50,000 volts.

I *believe* that a smaller gap (or finer electrode) will allow the 50k to jump sooner or easier. But I find it hard to believe that the coil produces less voltage because it "knows" the gap or final load is smaller and vice versa.

Doesn't the coil just get pre-loaded, so to speak, and discharges the same voltage each time when signaled by the distributor or computer? It has no idea (or time for that matter) to decide if the load is going to be small or large upon discharge and compensate for it in real time?

And as far as "generating an increasing voltage to the plug until it jumps the gap or arcs inside the coil or insulation of the plug" hint that a coil will increase the available voltage until it sparks...even if the gap is huge? Does it start small and increase until it fires? Or go big and tune it back until it stumbles?

Of course, I am not an auto mechanic nor an electrical engineer by trade so take what I say with a grain of salt.

I am always trying to learn more and add it to what I have learned (correctly or incorrectly) already.

 

Not sure about the new coils but the "OLD" coils would fire when the ground was opened up by the points allowing the magnetic field to colapse causing a secondary winding to produce a high output voltage. Newer coils use a capacitor triggered coil but the results are the same. The size of the gap determines the voltage across it and the coil will discharge it's stored energy across the gap. The bigger the gap the higher the voltage - about 40 volts per 0.001 inch at atmospheric pressure. More voltage is required at higher pressures and less voltage at partial vacuum. What happens is when the gap is smaller the spark will last longer and the current may be a little higher. When the gap is bigger the spark will be a little shorter in duration with a little less current but the actual energy will be greater P=I x V (power = current times voltage) so you get a hotter spark and ignite the fuel better IF you can make the spark plug fire at that bigger gap. Bigger gaps usually will make starting easier and ignite a leaner a/f mixture better since it makes a bigger spark and projects into the cylinder chamber further.

 

Thanks, Jan06xB!

 

If you run into a high cylinder pressure situation, like a high revving, high compression engine, or a boosted motor, you will quickly find that a short gap works wonders. I found that out years ago while racing serious drag motorcycles.
I just make it a habit to gap my stuff tighter than stock, probably doent do much for a street motor, but it cant hurt.
Also, what metal conducts better, copper, or irirdium? Better conductors, better voltage. My 06 xb came with the ngk copper u plugs, and I put in a fresh set after 10K, for 4 bucks, who cares..lol.

 

iridium is a better conductor. xb came with iridium platinum plugs from factory, not copper. Toyota has not use copper plugs for a long long time.

 

Not in the xB they aren't. You TC boys are lucky and get the iridium plugs, us lowly box drivers get the plain ol' copper plugs.

 

Yeah THAT'S what I thought I read too so Iridiums are going in. Should be interesting to finally SEE the plugs in my xB and to take off the engine cover. Hey I figure I don't need to change my oil (Synlube) for 13 more years or 135k miles then I should take care of the plugs while I am at it too.