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Shovelhead Kevin
Joined: Sun Dec 10th, 2017
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Kevin- Ranger plugs don't need to be indexed although you could if you really wanted to.
Because of the type of coils used, the spark plugs have reversed polarity on the right versus left cylinder banks. To save a tiny bit of money per vehicle, the factory once used two different plugs with platinum only on the correct electrode for each bank's ignition polarity. That meant that the left bank and right bank plugs were different and carried different part numbers.
To avoid confusion and possible (probable?) installation mistakes, the bank-specific plugs were not made available as replacements. Instead, double platinum, finewire platinum or iridium replacement plugs are readily available and provide long service life with either polarity. So, a set of spark plugs with a single part number can be used in both banks.
Thanks so much brother. That one post answered a multitude of questions.
I used to index plugs in our racing karts as well. Then again, methanol can make for some interesting tuning. ;)
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The good we do is never remembered, the bad...never forgotten.
1998 4.0 XLT ExtCab 4x4 {lil Red/Mine}
2005 Honda Civic {Hers/Ours/Spare}
2015 Hyundai Accent {Hers}
1980 80" Harley FXLR Custom {ALL mine!}