Iridium Sparkplugs in a 0520

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lbdb1a
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Iridium Sparkplugs in a 0520

Post by lbdb1a »

Does anyone have any experience with installing the 18mm to 14mm spark plug adapters so you can use 14mm Iridium Fine Wire plugs....?

Larry

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JAMES
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Re: Iridium Sparkplugs in a 0520

Post by JAMES »

I DONT NO THE ANSWER, BUT AS LONG AS U DONT THINK THAT SHYT CAME FROM THE MOON AND ITS GONNA RUN BETTER WELL BE OK :wink:
https://m.facebook.com/321ccc/?ref=bookmarks Wp383 268 rotator 3 bld WT/EX 14.4 perdator

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Re: Iridium Sparkplugs in a 0520

Post by GMAC 76 »

done it several times on lyc engines with good results it does give you a greater selection on heat range and thread length when using automotive plugs

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Re: Iridium Sparkplugs in a 0520

Post by TIGO541 »

I have the adapters in my motor. Im running a 14mm 3/4inch reach resistor. ($2 a piece) Just not possible in a 18mm unless you want to pay a fortune for them from an aircraft store. Large selection of plugs. No complaints
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lbdb1a
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Re: Iridium Sparkplugs in a 0520

Post by lbdb1a »

TIGO541,
What type 14mm plug are you using..iridium,platinum or standard copper...? Do you know what 14mm plug would have the same heat rating as the autolite 386...? And did you go with "long reach" steel adapters or copper...? or just the short reach steel or copper...?

Larry

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Re: Iridium Sparkplugs in a 0520

Post by TIGO541 »

I think they are NGK TR5. You want a 6 heat range in a NGK for normally aspirated. I have the long reach steel adapters (3/4). Got them from Abner Thornton at Keeners Machine. They are priced reasonably.
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gblack15
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Re: Iridium Sparkplugs in a 0520

Post by gblack15 »

Ok, for the ignorant of us. Why all the fuss about Iridium Plugs?

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lbdb1a
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Re: Iridium Sparkplugs in a 0520

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gblack15
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Re: Iridium Sparkplugs in a 0520

Post by gblack15 »

Interesting article, anyone using them and if so what differences have you noticed in performance?

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Re: Iridium Sparkplugs in a 0520

Post by jre1226 »

I went from swinging a 72 2 blade q at 2.75 to swinging a 74'' 4 blade q at the 3 mark just by changing 12 sparkplugs best investment of my life Id guess 300 HP gain lol

On a serious note I have not tried them on the 540 but did run one on a kx100 2stroke dirtbike I had and will never go back to platinum or copper burned alot cleaner and went about 3 years before changing it or even cleaning it with out any power losses I would love to try them on the boat not so much thinking I will gain more than 20 rpm if that just because how reliable it prove to be on a 2 stroke dirtbike. Just curious on anyones thoughts on any possible issues with the leaded gas. I did run the bike on av gas a few times with out any issues but wonder on a consistent bases will lead affect plugs

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Re: Iridium Sparkplugs in a 0520

Post by gblack15 »

GMAC 76 wrote:done it several times on lyc engines with good results it does give you a greater selection on heat range and thread length when using automotive plugs

What plug did you run and did you need an adapter? I am considering it for my 0360.

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Re: Iridium Sparkplugs in a 0520

Post by GMAC 76 »

gblack15 wrote:
GMAC 76 wrote:done it several times on lyc engines with good results it does give you a greater selection on heat range and thread length when using automotive plugs

What plug did you run and did you need an adapter? I am considering it for my 0360.
i used the E-MAG auto plug ADAPTERS with the copper washers from aircraft spruce part #08-06753-1/// these adapters allow you to use the 14mm auto spark plug in the 18mm aircraft plug hole ///E-MAG recomends using NGK brand 14mm plugs i do not remember the number on the plugs i used sorry/// i do remember one set was for a pumped up 360 using avgas the other set was a different number used on an 0-235 using automotive fuel the heat range was different because of the fuel being used but both worked out really well

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Re: Iridium Sparkplugs in a 0520

Post by Wild Bill »

This is one of the sites I found, haven't bothered to compare prices etc. yet.

http://www.sparkplugadapters.com/services.html

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Re: Iridium Sparkplugs in a 0520

Post by dusty burch »

jre1226 wrote:I went from swinging a 72 2 blade q at 2.75 to swinging a 74'' 4 blade q at the 3 mark just by changing 12 sparkplugs best investment of my life Id guess 300 HP gain lol

On a serious note I have not tried them on the 540 but did run one on a kx100 2stroke dirtbike I had and will never go back to platinum or copper burned alot cleaner and went about 3 years before changing it or even cleaning it with out any power losses I would love to try them on the boat not so much thinking I will gain more than 20 rpm if that just because how reliable it prove to be on a 2 stroke dirtbike. Just curious on anyones thoughts on any possible issues with the leaded gas. I did run the bike on av gas a few times with out any issues but wonder on a consistent bases will lead affect plugs
that is impossible ok here is one then I went from 87 to 93 and gained 2000 rpm's thats is some good gas

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Re: Iridium Sparkplugs in a 0520

Post by FrikkiDikki »

If you are using a magneto ignition, you'll want to use a NON-resistor plug. I've been using NGK BP6-ES and BP7-ES these are a 3/4" reach projected tip conventional plug ($2-3 each ). I should probably switch to the more expensive Iridium plugs, as these cheap ones only gave me an additional 50-60hp and I was kinda expecting a little more from this mod LoL!

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Re: Iridium Sparkplugs in a 0520

Post by lbdb1a »

Would be nice to get a good technical answer to a simple question......

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Re: Iridium Sparkplugs in a 0520

Post by FrikkiDikki »

To answer the original question, yes, I have been using the 18mm to 14mm adapters in my engine for about 8 yrs. They are homemade and work really well. Didn't mean to rub ya the wrong way.

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lbdb1a
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Re: Iridium Sparkplugs in a 0520

Post by lbdb1a »

Thanks for the note about using the inserts for 8 yrs.

I am installing extended reach inserts and will use 14mm, .750 " long reach plugs. When not using the boat i will install 14mm dehydrators in the top cylinders to control the moisture.

Larry

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Re: Iridium Sparkplugs in a 0520

Post by lbdb1a »

This is what i decided to go with.

Larry
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Re: Iridium Sparkplugs in a 0520

Post by FrikkiDikki »

Your adapters are better looking than mine. What brand and model # are your plugs?

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lbdb1a
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Re: Iridium Sparkplugs in a 0520

Post by lbdb1a »

The plugs are Bosch # BCH-9602 fine wire Iridium. I got them from Summit Racing for $4.95 each plus shipping of $9.95 for 13 plugs ie: $5.72 each...one spare for the tool box. Advance Auto wanted $7.48 including sale tax.

The extended sparkplug adapters item # 8FS-E-4TS were $5.65 each including shipping. http://www.sparkplugadapters.com/services.html.

I torqued the adapter to 25 ft-lbs and the plug to 15 ft-lbs.

Larry

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Re: Iridium Sparkplugs in a 0520

Post by MJD291 »

lbdb1a wrote:The plugs are Bosch # BCH-9602 fine wire Iridium. I got them from Summit Racing for $4.95 each plus shipping of $9.95 for 13 plugs ie: $5.72 each...one spare for the tool box. Advance Auto wanted $7.48 including sale tax.

The extended sparkplug adapters item # 8FS-E-4TS were $5.65 each including shipping. http://www.sparkplugadapters.com/services.html.

I torqued the adapter to 25 ft-lbs and the plug to 15 ft-lbs.

Larry
Please give us an update of this when you get it installed. I would love to hear the outcome.
I LOVE THE SMELL OF AV GAS IN THE MORNING. IT SMELLS LIKE..... VICTORY

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lbdb1a
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Re: Iridium Sparkplugs in a 0520

Post by lbdb1a »

This is the 14mm dehydrator you install in the plug hole when the boat is inactive for a month or so. The beads turn pink when they have absorbed moisture . You just remove the beads and heat them up with a heat gun or in the oven and they will turn back to blue for reuse.

It only took about 3 weeks for them to turn pink up here in north florida.


Larry
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Re: Iridium Sparkplugs in a 0520

Post by FrikkiDikki »

Keep us posted on how these work as to being the the proper heat range. Myself, I wouldn't use a resistor plug on a magneto ignition (I have used RH-12's in the past and experienced more fouling )
However, I currently am using an impulse mag on the topside plugs (which I use for cranking) and a automotive type points/ coil/ distributor ignition driven off the tach drive to fire the bottom plugs.

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Re: Iridium Sparkplugs in a 0520

Post by lbdb1a »

I converted from an 18mm Autolite 386 heat range to the Bosch M8ACO heat range 8 per the chart below. To use the "long reach" 14mm Iridium Bosch with a heat range of 8 i used the BCH 9602 .

Possible spark plugs:
NGK: A6
NGK: AB-2
AC Delco: C86
AC Delco: C86S
AC Delco: S85F
AC Delco: C87
AC Delco: C88
AC Delco: C88L
Autolite: 386
Autolite: 2775
Autolite: 3035
Autolite: 3136
Autolite: 376
Autolite: 3116
Autolite: 378
Bosch: M8ACO
Bosch: M8AC0
Champion: D16
Denso: L14R-U
Denso: M14
Denso: MA16R-U
Denso: L14-U
Motorcraft: BT8
Napa: X981
Napa: X571
Napa: X581
Prestolite: 18-08-01
Prestolite: 18-09-01
Prestolite: 18-10-01
Stitt: 897
Stitt: 82
Stitt: 86


Details about your spark plug:
Type: IND.
Thread size: 18mm (0.70866 inches)
Hex size: 1 inches (25.4 mm)
Reach: 12MM inches (304.8 mm)
Seat type: GASKET
Projected tip: NO

Larry

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