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Spark Plugs

   
Old Apr 6, 2017 | 02:25 PM
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Default Spark Plugs
Hey newb question here. ive noticed at Harley they sell ( screamin eagle spark plugs )

as far as a built engine goes id assume youd need a hotter plug but for a factory 103 with a stage 1 will a hotter plug benefit in anyway?

what are the screaming eagle plugs? its not like the MoCo is in the spark plug business.....
 
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Old Apr 6, 2017 | 05:56 PM
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At least in the car world when you build a car for increased HP, most times a cooler plug is used to help prevent pre-ignition. Just one step cooler, nothing drastic.
 
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Old Apr 6, 2017 | 06:56 PM
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Madduc is correct. On performance mods you typically go cooler. You typically need a compression increase to need to go cooler.. In the case of a stage 1, you can pull the plugs and look at them if you want. White is OK but bleached, eroded or gray ***** on the electrode are bad. Side strap should change color mid way.
 
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Old Apr 6, 2017 | 09:07 PM
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OE plug will be just fine
 
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Old Apr 6, 2017 | 09:07 PM
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Proper tune, stock plugs.
 
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Old Apr 6, 2017 | 09:24 PM
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Originally Posted by Max Headflow
Madduc is correct. On performance mods you typically go cooler. You typically need a compression increase to need to go cooler.. In the case of a stage 1, you can pull the plugs and look at them if you want. White is OK but bleached, eroded or gray ***** on the electrode are bad. Side strap should change color mid way.
I should have made my point more clear. Stage 1 is not a serious performance mod IMO.. Bump the CR to 10.5 to 1 and get the CCP over 200 and you might be looking for cooler plugs.

The rest was more about reading the plugs to see if you have an issue the current state of tune.
 
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Old Apr 7, 2017 | 11:12 AM
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RA8HC Champion,,, The go-to Plugs for my guy that Owns / Operates a Tuning School...

$ave $$$ Champion makes Plugs for HD...
 
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Old Apr 7, 2017 | 04:24 PM
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I use RA6HCs but then I don't own a stage 1.
 
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Old Apr 8, 2017 | 01:39 PM
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Do the RA8HC work with the knock detection ? If so I might switch over. I don't have a local shop to get the Harley plugs from.
 
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Old Apr 8, 2017 | 08:50 PM
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Just ordered some 10R12A, (32335-04), which are out if the VRod for a 107 10.8cr build
 
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