flickroll

flickroll

Well Known Member
I'm going to the Dark Side and installing dual P-Mags in my -8. I bought a set of el-cheapo NGK BR8ES automotive spark plugs for my parallel valve O-360. I wondered if anyone is using a 'higher performance' automotive plug in their airplanes. The local Advance Auto has Bosch platinum dual electrode and quad electrode plugs, but I'm not sure if these are the proper heat range, etc. In any event, other than the 2 plugs mentioned in the P-Mag installation manual, is there another plug that offers really good performance. I seen 'racing plugs' mentioned on VAF, but no part numbers. Oh yeah, I also bought Bill Repucci's E I Commander EI control module. The device is slick, and Bill offers absolutely tremendous customer service/support. Thanks
 
NGK BR8EIX work great as well.. (Iridium plugs).. probably better than the "cheapos" ... but you may have to see it for yourself..
 
NGK is the best brand automotive spark plug out there IMO. Stay away from Bosch. I second the vote for the NGK iridium for long-life auto plugs.
 
I just bought 4 Denso IK27 spark plugs from Jegs.com for 13.99 each. I have a LS Plasma III in my RV-8. These are iridium plugs which supposedly have a much higher heat tolerance and better spark exposure during the combustion cycle. I googled info on iridium plugs and heat ranges and got a little education first, then called Klaus at Lightspeed. Klaus recommends the Denso plugs (formerly Nippon-Denso). He says the NGK's are cheap - that's why you can get them anywhere. The 27 heat range is appropriate for my 9.0:1 pistons. If you have standard 8.5:1 pistons, a 24 heat range may be better. I originally had the standard Lightspeed issue Denso W24EMR-C plugs which are for low and standard compressions. The heat range numbers are contrary to logic in my opinion. A 24 is a hotter plug than a 31. Heat range refers to a plugs ability to dissipate heat, so a 24 will dissipate heat better than a 31 (more metal, less insulator in the core above the electrode to carry heat up through the head). The higher the compression ratio the cooler the plug needs to be (less heat dissipation?? ). Most engines on RV's will use a 24, 27, or 31, depending on compression. If you are running a racing engine, you may need a 34 - or higher. Klaus recommended the IK27 for my engine and he certainly knows more about this than most of us.

Scott
RV-8FB
 
Heat range

I was having this same discussion about 2 days ago on which plugs to run with a Plasma II ignition. I did little research on spark plug heat range and the statement "The heat range numbers are contrary to logic in my opinion. A 24 is a hotter plug than a 31. " is correct for Denso & NGK plugs.

However, American plugs - Champion, Autolite, etc are the opposite: higher numbers are hotter.

My Lightspeed came with Denso W27EMR-C plugs. I just replaced them (93 hours) with another set of the same type which I had on hand. I'm going to try the Denso IK27 on the next go around.
 
flickroll said:
I'm going to the Dark Side and installing dual P-Mags in my -8. I bought a set of el-cheapo NGK BR8ES automotive spark plugs for my parallel valve O-360. I wondered if anyone is using a 'higher performance' automotive plug in their airplanes...
Click to expand...

As I understand it, the iridium plugs are only "better" because they are consistently good over the very long life of the plug. They are all the rage in the automotive world because cars in general are becoming increasingly "maintenance free", and the iridium plug in particular provides exceptionally long life with zero maintenance. In other words, with exotic plugs, you are paying for long life and zero maintenance... Hardly a consideration in aircraft engines that are opened up and looked at regularly.

Having said that, I run the "cheap" BR8ES plugs as well, but I replace them at every condition inspection so they are always in new condition. I would like to see data that proves there is a measurable performance difference between a fresh set of correct conventional plugs and that of the most expensive exotic plugs you can find in a typical aircraft engine. The biggest bang for the buck is getting to the electronic ignition and ANY plug that can deliver the spark... Going to an exotic plug is likely a case of significantly diminished return. In other words, if it's strictly performance, the exotics are likely not worth the investment.
 
And remember that if you run 100LL you may have to clean this out of those very expensive plugs without damaging them.

I'm thinking the cheap disposable plugs are the way to go for this reason..I mean changing them twice a year is only $20 per year or so.

Frank
 
frankh said:
And remember that if you run 100LL you may have to clean this out of those very expensive plugs without damaging them.


Frank
Click to expand...

So true... In cars, the iridium plugs blast away carbon build up with their super hot tip, but I wonder if they will do the same with lead? And if not, how can you clean them without damaging the tip?

Anybody running the iridium auto plugs care to comment?
 
How is it done??

Not a hijack, but how do you guys reduce the spark plug opening to accept the NGK plugs? I know that ECI offers the cylinders bored for 14 MM plugs, so I assume some are using an adapter of some sort.

Thanks for shedding light,
Chris
 
NGK

I've found NGK to be the best plug for my application (Lycoming) with LSEI Plasma II. I run the BR8EIX Solids which are Stock # 6747 which I prefer over the screw on tops. They run $6.99 ea.



flickroll said:
I'm going to the Dark Side and installing dual P-Mags in my -8. I bought a set of el-cheapo NGK BR8ES automotive spark plugs for my parallel valve O-360. I wondered if anyone is using a 'higher performance' automotive plug in their airplanes. The local Advance Auto has Bosch platinum dual electrode and quad electrode plugs, but I'm not sure if these are the proper heat range, etc. In any event, other than the 2 plugs mentioned in the P-Mag installation manual, is there another plug that offers really good performance. I seen 'racing plugs' mentioned on VAF, but no part numbers. Oh yeah, I also bought Bill Repucci's E I Commander EI control module. The device is slick, and Bill offers absolutely tremendous customer service/support. Thanks
Click to expand...
 
Auto spark plugs & SuperConducter Wire w/ std. mags

Has anyone had success (or failure) running auto plugs and auto spark plug wiring with standard mags?

If so, what would the spark plug gap be? Same as for aviation plugs? Presumably the plug gap has to be something that the (not very) high tension voltage produced by a mag could reliably jump.

I am thinking of running auto plugs on top to start to see how they work out. I like the idea of resistor plugs.

Larry
 
Radomir said:
NGK BR8EIX work great as well.. (Iridium plugs).. probably better than the "cheapos" ... but you may have to see it for yourself..
Click to expand...

What gap do you use with these plugs? .030 - .035 as per the PMag manual, or something different? Thanks
 
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Plugs of choice

Here are a couple plugs of my choice on my application
NGK Iridium Spark Plug
P/N: NGK-2743 PFR6J-11 GAP @ .026?
The automotive application: 1991-1999 Mitsubishi 3000GT Twin Turbo I ran these plugs for over 230 hours on my blown IO-540 with no issues. I just changed over to experiment with the colder Denso IK31 GAP @ .026? for a fuel & boost increase. Denso has more selection of heat ranges to dial your H/R preference in.

Nippon Denso Racing Iridium:
Hottest 5304 - IK20 equivalent to NGK-2743
5311 - IK24
Average 5312 - IK27
5321 - IK31
Coldest 5322 - IK34

Thomas S.
www.g3ignition.com
 
G3i Ignition said:
Here are a couple plugs of my choice on my application
NGK Iridium Spark Plug
P/N: NGK-2743 PFR6J-11 GAP @ .026?
The automotive application: 1991-1999 Mitsubishi 3000GT Twin Turbo I ran these plugs for over 230 hours on my blown IO-540 with no issues...
Click to expand...

Have you compared the iridium to the equivalent "conventional" NGK? If so, what were the benefits of the iridium?
 
I am still waiting for a definitive way to determine if one spark plug is better than another.
 
If in doubt go cheap...You can always go expensive later..except in this case there will be no reason to...:)

Frank
 
A test idea

How about this for a test, set up one ignition with the iridium, and the other with the regular NGK's and see if there is an RPM difference on the "mag" check.

Hans
 
It would never be a mag check...? EI iridium plugs hands down, there is no question... :)



nucleus said:
How about this for a test, set up one ignition with the iridium, and the other with the regular NGK's and see if there is an RPM difference on the "mag" check.

Hans
Click to expand...
 
How would there be a difference?...a plug either fires or it miss fires... If the plug lights the fire every time during the mag check then the drop will be identical in each case. With two EIs set up with the same igition advance then there will be no difference.... Now if the iridiums last ten times longer then you'll eventually get a miss fire on the cheap plugs... But I've had 200 hours on the cheapos for a buck 20 apiece. Why would you any different?
 
You missed my point if you're referring to my post... if your checking EI drops there would never be a mag check regardless of plugs.


frankh said:
How would there be a difference?...a plug either fires or it miss fires... If the plug lights the fire every time during the mag check then the drop will be identical in each case. With two EIs set up with the same igition advance then there will be no difference.... Now if the iridiums last ten times longer then you'll eventually get a miss fire on the cheap plugs... But I've had 200 hours on the cheapos for a buck 20 apiece. Why would you any different?
Click to expand...
 
?

frankh said:
How would there be a difference?...a plug either fires or it miss fires... If the plug lights the fire every time during the mag check then the drop will be identical in each case. With two EIs set up with the same igition advance then there will be no difference.... Now if the iridiums last ten times longer then you'll eventually get a miss fire on the cheap plugs... But I've had 200 hours on the cheapos for a buck 20 apiece. Why would you any different?
Click to expand...

Frank if you have a bigger spark with the expensive plugs then you should have less drop when running on that ignition alone... If the quality of spark did not matter then you would get the same drop on both sides if you had a mag on one side and a pmag on the other, which is not what happens in the real world.

LifeofReiley said:
You missed my point if you're referring to my post... if your checking EI drops there would never be a mag check regardless of plugs.
Click to expand...

Hence the quotation marks around the word "mag" in my post.
 
nucleus said:
Frank if you have a bigger spark with the expensive plugs then you should have less drop when running on that ignition alone... If the quality of spark did not matter then you would get the same drop on both sides if you had a mag on one side and a pmag on the other, which is not what happens in the real world.



Hence the quotation marks around the word "mag" in my post.
Click to expand...

I'm not sure I agree..I think the different RPM drop between an EI and a mag is due to the fact that the mag is fixed at 25 degrees...My assumption the timing on the EI is nearer the optimum (say 10 degrees) at 1500RPM.

Thus the drop on the mag would be greater cus it is making less power than when running on the EI.

So my contention is the spark itself makes no difference..it fires or it doesn't. Now I can see that with a rich mixture and a small plug gap (on a mag) it may stumble a bit more because the plug is getting fouled perhaps.

But the difference between cheap plugs running say a 35 thou (big) gap and more expensive plugs running the same gap..then where is the difference?

Frank
 
The only difference with iridium plugs is longevity. I run BR8ES and quit changing them during condition inspections, since they weren't wearing out.
 
Interestingly (to me anyway), my CR250R (two stroke motocross bike) takes a BR8ES as standard. I run a BR8EIX. I've found that the EIX is significantly less prone to fouling. The two stroke has a comparatively huge carb, very aggressive porting (50hp from a 250cc single requires such measures I suppose) and rich jetting and will wet-foul somewhat easily when cold or when ridden more slowly than intended (for example, trail riding with my wife). I've never really worn out a plug of either type in the MX bike, but have fouled ES plugs. I have never fouled an EIX plug. My street bike will wear out plugs. It will go about 15k miles on the stock EK (like an ES, but has two ground straps and they are beside the center electrode rather than over it). I currently have Brisk plugs in it. They still work as new with about 40k miles on them (IIRC). I don't think they work better (they likely have improved fouling resistance, but the fuel injected street bike isn't terribly prone to fouling) in terms of performance.
 
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Spark Plug Rep.

I am the rep for Champion automotive. The only thing the precious metals plugs will do is like others have said is to add to life of the plug. They were developed for the high energy systems that have a lot stronger spark. This platinum or the iridium will keep the spark from eroding the tips with this stronger spark.
There are some performance plugs that we use for racing, but these would not help with what we are using them for.
Champion Aviation is another company.
Keep using the regular ones and they will be fine. NGK,Autolite,Nipo, or Champion are of equal quality. AC does not make plugs. They are made by one of the other companies.
 
Auto plugs with standard mags

Gary Bricker said:
I am the rep for Champion automotive. The only thing the precious metals plugs will do is like others have said is to add to life of the plug. They were developed for the high energy systems that have a lot stronger spark. This platinum or the iridium will keep the spark from eroding the tips with this stronger spark.
There are some performance plugs that we use for racing, but these would not help with what we are using them for.
Champion Aviation is another company.
Keep using the regular ones and they will be fine. NGK,Autolite,Nipo, or Champion are of equal quality. AC does not make plugs. They are made by one of the other companies.
Click to expand...

Gary do you have an opinion re auto plug use with standard magnetos?

Larry
 
Std plugs w/Mags

Std Mags don' t put out the fire that late model auto electronic iginitions do so std plugs should be fine. I have regular aircraft plugs in my RV and Debonair. So no experence with auto plugs.
 
Aggressively Leaned, Higher RPM with the Iridium Plugs

Okay, yesterday I remembered to aggressively lean on run-up on my "mag" check. I have NGK BR8EIX Iridium plugs on one p-mag and regular NGK BRE8's on the other p-mag. Both sets are brand new. Identical RPM drop with a normal mixture. Aggressively leaned, the Iridium plugs have 60-70 more RPM than the BRE8's.

My conclusion is the same power with a smaller electrode makes for a bigger spark. That bigger spark is useful igniting a very lean mixture. The wear resistance of the Iridium is what allows the use of the small electrode. I will upgrade my other plugs soon.

Hans
 
BR8EIX gap?

When using the BR8EIX iridium plugs with a plama II (8.5 comp), what do you gap these to? Is there any difference from the standard denso plug gap?
 
ALERT - INFLIGHT SPARK PLUG FAILURE

Hello VAF

I have been using Desno W27ESR-U in my RV-7A "Dual Light Speed EI". Yesterday I had a spike on my #2 EGT - Verified a bad "left" EI system & headed back to the airport (10mins out). Landed, took off the cowls & found the spark plug wire off #2 bottom plug.

Upon further investigation, I found the aluminum nipple (the part that attaches to the plug wire) in the boot and all the threads stripped off of it. Looking at all the other plugs I noticed all the aluminum nipples were loose (showing signs of eminent failure). About 100 hours on the plugs

So I looked at the older style plugs I was using Denso W24EMR-C. These nipples do not look like threaded aluminum & they do not look like they will separate.

I further looked at new "out of the box" aluminum nipple Denso W27ESR-U. They look like they are threaded and crimped by the factory, as they have an oval shape (not round).

I looked at NGK BR8ES - they have aluminum nipples. I looked at NGK BR9ES and they have the same steel nipples like the Denso W24EMR-C


I suggest if you have aluminum nipples on your auto spark plugs; that you check to see if the threads/nipples are worn or loose. I will no longer use spark plugs with thread/crimped aluminum nipples.

2h5tsw4.jpg


fz8461.jpg


1zxp5eb.jpg
 
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Good photos Clark. I have used the threaded-on nipples for awhile in one of our EI airplanes, but I took time to score the threads to sort of "jam" the nipples on. They didn't come off, but I did get some radio interference that went away when I switched to the solid nipple plugs. I am only going to use the solid-nipple plugs from now on, since they are available - but if you go into the auto parts store, you need to ask for them. NGK has two different p/n's for their BR8ES plugs, 3961 and 5422. 3961 has the fixed terminal nut while the 5422 is removable. Most auto parts store consider them identical, and stock whichever shows up. I found them consistently at Rockauto.com .

Paul
 
Thanks Paul

Paul - Thank You for that information about the BR8ES - I will make note that there are two different part # for the same plug designator. That is great information to have!

I can't take credit for the photos - My friend James who is a Professional Photographer took them in my hangar last night.

We looked closely at the nipple that came off - The threads on inside of the nipple were worn off & there seemed to be a carbon buildup on the inside of the nipple (we assumed from arcing).
 
Same type of testing equipment (Theory) used in testing aircraft type plugs, no explanation necessary just observe the video. Iridiums rock! :D
 
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