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Fueling was 11.98 afr just below peak torque, 12.24 from about 4800 rpm and 12.45 afr from 5200 till 6600 rpm. This made 379 rwhp and 357 rwtrq. This is what the plugs saw for 99% of their life.
1.5 weeks ago I changed the afr to 12.18 below peak torque, 12.44 at the 4800 rpm cell and 12.62 from 5200 till 6600 rpm.
I'm not sure if that 1.5 weeks would clean up the fuel ring of 5 months of being at the richer afr but I thought I'd mention the background info in case.
The 7 consistent fuel rings are 0.060" to 0.070" thick and the lone one is 0.050" thick.
I hope the lone one is from cylinder 7 or 8 as I wasn't planning on doing this check when I leisurely changed the plugs to go colder so I didn't label which cylinder had which plug.
This is an NA motor, does the thickness correspond to too rich, just right?
Need to put fresh plugs in, push car through staging lanes, start at last possible moment, make a pass, shut it off after you cross the line and tow it back to the pits, then pull the plugs to read.
Ok going to do that in spring but that discrepancy you see on that one spark plug, is that something that is normally seen in one of the rear cylinders due to heat?
10-08-2016, 12:42 PM
Help me in reading the fuel ring-spark plug 
