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Spark plugs and feedback knock values

1147 Views 3 Replies 2 Participants Last post by  krisr33
So I recently did some logs on my 04 sti (stage 2) and noticed my feedback knock numbers were hitting around -6 on fast WOT pulls. So I desided that I would check if there were anything wrong with my spark plugs. When I got the first one out I noticed they were ngk lfr5aix. So I am wondering if having the "5" series plugs could be causing the problem? Since they are 1 heat range higher than the stock plugs. Also would u recommend running one temp range lower maybe the ngk lfr7aix?
1 - 4 of 4 Posts
Just run stock heat range for your stage 2 setup.
Isn't the plug that I mentioned was in there currently equivalent to stock minus the heat range?
1 - 4 of 4 Posts
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