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Forum nameTurbo/Nitrous Tech
Topic subjectQuick Question on plug color
Topic URLhttps://forums.2gnt.com/dcboard.php?az=show_topic&forum=i8&topic_id=36880
36880, Quick Question on plug color
Posted by RxR_Eclipse, Jan-04-03 08:53 AM
Ok I just pulled my first set of BKR7E-11's. The ends look light grey. Is this normal?...Im gaped at 32.
36881, RE: Quick Question on plug color
Posted by DeanoD, Jan-04-03 09:27 AM
NGK answers

http://www.ngksparkplugs.com/techinfo/spark_plugs/faq/faqread2.asp

As many people have previously stated:

White tip-lean
Light gray-slightly lean/stoich
medium gray-good fuel burn/safe
dark gray-bit rich/safe
charcole color-rich
black-too rich
wet black-extremely rich

This is only for the tip. The inside insulator should always be black. If the plug tip is red, then you are using octane boosters. Also the tip should be smooth and not pitted/rough. If it is, then you are experiencing some detonation.

My plugs are are medium gray in the winter 35-50F outside. This because of the colder denser air requiring more fuel, but the intakes temps are low, so my spark advance is 17-18 degrees(below 1600F at 11psi). When the hot 90-100F humid summer comes the air is less dense which requires less fuel, but my intake temps are probably really high(1600F at 9psi), which causes my timing to retard much more than in the cool temps. This causes my spark plugs to look charcole in color. This is because fuel is not being burned totally.

Hope this helps
36882, RE: Quick Question on plug color
Posted by RxR_Eclipse, Jan-04-03 02:49 PM
Thanks. Answers my question. Mine look just like that first one on the page.. except I have the "V" groove.
36883, RE: Quick Question on plug color
Posted by MotoFool, Jan-04-03 07:25 PM
your plus are fine rxr i like to opt for a tad bit darker plug color because i like to run slightly rich to stay away from going to elan and going boom, thats the way ive alwasy tuned my race cars a tad rich for the most part to keep it safe id rather loose the race and drive my car home then win and not drive it home ya know??

36884, RE: Quick Question on plug color
Posted by RxR_Eclipse, Jan-05-03 02:40 AM
Yea I turned my fuel pressure up by 3lbs yesterday. :) Keep it on the slightly rich side of things.
36885, RE: Quick Question on plug color
Posted by MotoFool, Jan-05-03 06:54 AM
yea thats a smart decision, dont need to play around with lean conditions on that stock internaled motor