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Old Oct 17, 2015 | 10:13 AM
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Default Spark plugs
What is a good spark plug for high compression? 1991 Softail Custom
 
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Old Oct 17, 2015 | 11:16 AM
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look at some SE's that for you engine..
 
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Old Oct 17, 2015 | 03:43 PM
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Anyone else want to chime in?
 
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Old Oct 17, 2015 | 07:15 PM
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I always found that Autolites worked well, regardless if bone stock or modified.

Most of the newer plugs are just overpriced gimmicks that yield the same or worse performance.

I find the Autolites have a consistency to them that is sometimes lacking in other brands.

They are also readily available virtually anywhere.
 
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Old Oct 17, 2015 | 08:35 PM
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Originally Posted by oct1949
look at some SE's that for you engine..
Correct, they have them with the specific heat range for standard and for high compression.
 
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Old Oct 17, 2015 | 08:43 PM
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Originally Posted by 1004ron
Correct, they have them with the specific heat range for standard and for high compression.
I went down to Sacramento Harley Davidson and picked up a set of SE 32188-10 and put them in. The sells parts was very sceptical selling them to me. I had to have someone else double check to make sure he looked up the right plugs. Bike seems to run better. Kinda seems like its running less lean. Could that be?
 
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Old Oct 17, 2015 | 08:52 PM
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Spark plugs have no effect on lean or rich fuel air mixture. I don't care if we are talking about a flat head or a wet head.

Heat range will affect how it burns. Most spark plugs are available in three heat ranges. A high compression engine does better with cooler heat ranges. The spark plug gap is also a factor and can be adjusted to suit the engine, especially when you are dealing with modified/ high performance.

Avoid multi electrode and other gimmicks.
 
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Old Oct 17, 2015 | 10:43 PM
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I just threw in a pair of $9. iridium from ngk and notice NO difference
Next time or sooner ging back to good ole copper tops
 
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Old Oct 18, 2015 | 07:50 AM
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I've been running NGK Iridiums. My TC88 is stock. It seems like it does start better but as far as performance, I couldn't tell any difference.

I've always been a fan of Autolites as well. My 460 Ford as always liked them.
 
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Old Jan 16, 2016 | 07:57 PM
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I'm having a problem still with the spark plug fouling up.

Screming eagle plugs
<a href="http://s175.photobucket.com/user/redjft/media/Mobile%20Uploads/IMG_20160116_174538_zpsmuoevmhy.jpg.html" target="_blank"><img src="http://i175.photobucket.com/albums/w157/redjft/Mobile%20Uploads/IMG_20160116_174538_zpsmuoevmhy.jpg" border="0" alt=" photo IMG_20160116_174538_zpsmuoevmhy.jpg"/></a>

Auto lite 65 (were in bike when I bought it)
<a href="http://s175.photobucket.com/user/redjft/media/Mobile%20Uploads/IMG_20160116_174626_zpsyfbudznw.jpg.html" target="_blank"><img src="http://i175.photobucket.com/albums/w157/redjft/Mobile%20Uploads/IMG_20160116_174626_zpsyfbudznw.jpg" border="0" alt=" photo IMG_20160116_174626_zpsyfbudznw.jpg"/></a>

An these plugs I put in ran it for about 10 mins and rode 1 mile around the block. NGK 5534
<a href="http://s175.photobucket.com/user/redjft/media/Mobile%20Uploads/IMG_20160116_174717_zpsyqbdqfbt.jpg.html" target="_blank"><img src="http://i175.photobucket.com/albums/w157/redjft/Mobile%20Uploads/IMG_20160116_174717_zpsyqbdqfbt.jpg" border="0" alt=" photo IMG_20160116_174717_zpsyqbdqfbt.jpg"/></a><a href="http://s175.photobucket.com/user/redjft/media/Mobile%20Uploads/IMG_20160116_174703_zpseufesgif.jpg.html" target="_blank"><img src="http://i175.photobucket.com/albums/w157/redjft/Mobile%20Uploads/IMG_20160116_174703_zpseufesgif.jpg" border="0" alt=" photo IMG_20160116_174703_zpseufesgif.jpg"/></a>
 
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