Spark plug questions

[Dino]

After all these modifications and running different carbs I thought it'd be best to pull the plugs again.  I took pics with and without flash.  They look kinda light to me and the car does seem to be running lean.   These are the plugs from cylinders 5, 7, and 8.  NGK XR5 with a few thousand miles on them.  Any reason I should change them or are they still good?  Stock engine with 280/474 cam and headers.  If I need new plugs I guess I should stick with the same kind?

[Dino]

2 more

[69wannabe]

I just swapped in a new set of NGK's into my charger big block. The one's I pulled out of mine looked very similar to yours. Look's like the carb maybe a tad bit lean or maybe the heat range is a little hot for the engine. I swapped some champion J12's for a set of NGK 6's. I went to a one step cooler plug but haven't driven it but around the block so I will see how it goes after driving it awhile and see what they look like. Maybe someone else will chime in and have a better answer!!

[flyinlow]

In my  professional Mopar Mechanic opinion ( ) ........wait for it........wait for it............their fine.

They look similar to the ones I took out of the '70. The only reason I replaced them is the the car has headers and I am too lazy to file the electrodes sharp again so for $24 I just put new ones in.

If you are trying to get a WOT A/F ratio reading ,you need to put a fresh plug or two in run down the quarter mile, put  the car in neutral ,shut it off, sit there until it cools and then read the plug , before you drive home.  PITA.

There are some ash deposits which might be a little oil consumption or todays crappy fuel and there is a little soot on the bases , somewhat normal and I know from your other posts your engine has been running rich in the past. Nothing to be overly concerned with IMHO.

[A383Wing]

the color is fine....move on to other things

[Dino]

Thanks guys, that saves me a few bucks and the hassle of getting #3 out.   

It did run rich before so I wasn't too worried about the base either, I also had valve cover leaks, now fixed (mostly) but the plugs are still dirty from it.

I think I may have set the TQ's metering rods too lean, I forgot I adjusted that tree thingie.  I'll also richen the idle mixture a bit.  It may explain why it's so hard to start after it sits a few days.  It must be lean all over the board.

[A383Wing]

if it was lean like you are thinking, plugs porcelain would be whiter....the only way to tell how rich or lean it's running is to put O2 sensors in the exhaust and measure the fuel to air ratio with a gauge

I would be happy with what your plugs are saying right now

[Dino]

Hmmm good point.  I only guess it's lean because of the way it runs, but that doesn't mean the problem does not lie elsewhere.  I'll reset the metering rod tree to stock specs and leave it there.  The carb should be back to tock specs now.