Spark plugs for STD heads

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texasbobber
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Spark plugs for STD heads

#1

Post by texasbobber » Fri Apr 28, 2006 5:30 pm

Description: What long reach plug are you using for STD heads?

What long reach plug are you using for STD heads?
Right now I'm using Champion RN12YC (404's). I don't know if it's a hot or cold plug, some of the cross reference charts are confusing. I have a Power Arc electronic ignition in a 74" pan, kicker only.
I don't know if resistor plugs are needed for the electronic ignition either.
How bout ya'll?
TxRR



fourthgear
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Re: Spark plugs for STD heads

#2

Post by fourthgear » Fri Apr 28, 2006 7:05 pm

I think resistor plugs and wires are just for radio interference on cages. I don't think you need them, I kinda like the static on cage stereos when I pull up next to them with my copper core wires. I'm running points, electronic ignitions use graphite cores in the wires as you probably know.

caschnd1
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Re: Spark plugs for STD heads

#3

Post by caschnd1 » Fri Apr 28, 2006 9:00 pm

From the PowerArc web site:

SPARK PLUG WIRES
Choice of spark plug wires is an important consideration when using an electronic ignition system. You must use carbon core resistor spark plug wires. Solid or Spiral wound wires will damage the ignition module and void the warranty!

SPARK PLUGS
You must use a resistor spark plug with electronic ignitions. Stock spark plugs are resistor type plugs and will work. Spark plug gap should be limited to as small as possible, while still maintaining performance.
A wide spark plug gap can cause the following problems: Hard cold starting, misfires during rich or lean fuel conditions, and reduction of upper rpm range.

Initial settings for spark plug gaps are:
Single plug Multi-Spark 0.028-0.032
Dual plug Multi-Spark 0.025-0.030

mbskeam
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Re: Spark plugs for STD heads

#4

Post by mbskeam » Sat Apr 29, 2006 4:41 am

here is a handy plug chart also.......
aint the internet grand.
plug chart1.jpg
plug chart1.jpg (41.07 KiB) Viewed 1716 times
mbskeam

Billy
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Re: Spark plugs for STD heads

#5

Post by Billy » Sat Apr 29, 2006 6:25 am

Mbskeam-

Handy chart, I have one kinda similar in my tool cabinet, course it includes the ever popular Flatties & knucks, too.. ;D

I'd copy it & save it if someone doesn't have one.. .. FWIW

panhead
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Re: Spark plugs for STD heads

#6

Post by panhead » Sun Apr 30, 2006 4:51 pm

TxRR,

I use NGK BP5ES on my dual-plug STD's (with electronic ignition)

texasbobber
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Re: Spark plugs for STD heads

#7

Post by texasbobber » Mon May 01, 2006 3:33 pm

Post by texasbobber on May 1, 2006, 3:33pm

thanks everyone, I'm gettin some NGK resistor plugs.
Craig, thanks for the Power Arc info which I had folded up laying on a workbench. (I don't read directions according to my OL -haha.)
TxRR

grottorian
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Re: Spark plugs for STD heads

#8

Post by grottorian » Mon May 01, 2006 7:53 pm

Would the same wires & plugs be best for dual plug STD's with single points ign. ? I'm running Champion RN12YC's & Accel 8.0 mm graphite wires now. It runs good.

harleydoug

Re: Spark plugs for STD heads

#9

Post by harleydoug » Wed Jun 07, 2006 4:35 pm

I use the Champion #4071 in my duel plugged STD heads with a crane hi-4 in a reverse rotation distributor
the 4071 is a RN12 YC in a copper "truck" plug, but it has the smaller 5/8 hex, so you can get at it in the pushrod side. I gap all 4 plugs at .035

Please use the wires made especially for electronic ignition. The "stray" voltage from the other wires will confuse and destroy your electronic unit

Edaddy
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Re: Spark plugs for STD heads

#10

Post by Edaddy » Thu Dec 07, 2017 7:47 pm

Just my .02 after much research online. Add these to the list. The Autolite 3926 are reputedly the official ones recommended by Lou at STD. I ran the 3928's - just a bit hotter for my previous low compression pistons. With new higher compression pistons in my current rebuild will probably run standard ones.

ND W9P-U
Autolite 3926


Edit - running standard ignition so your mileage will vary with electronic ignitions - just this is one of the few places online with info about STD Panhead heads and wanted to stash this info here.

Edaddy
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Re: Spark plugs for STD heads

#11

Post by Edaddy » Thu Dec 07, 2017 8:08 pm

panhead wrote:
Sun Apr 30, 2006 4:51 pm
TxRR,

I use NGK BP5ES on my dual-plug STD's (with electronic ignition)
Was looking for some inexpensive sparkplugs for testing during the first few startups - these will be great!! On Ebay for $2.19 each.

Edaddy
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Re: Spark plugs for STD heads

#12

Post by Edaddy » Fri Dec 08, 2017 5:14 pm

Edit - got home and double checked the Autolites - 3924 are the ones recommended by Lou Tractenburg - was running 3926 in my low compression setup.

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