checking plugs what to look for?

[331 stang91]

So I have been messing with the fuel pressure allitle. First how long (miles) Would it take till the plugs changed colorc to indicate rick lean or just right? Also how can I read a plug I always seem to forget this give me a color indication for rich lean or right on THANKS!

 

[stanglx2002]

black = rich
brown/gray = normal
white = lean

 

[331 stang91]

thanks. anyone know how long it takes to change after you changs the pressure?

 

[kck6894]

to get an acurate reading you should change plugs. Also when reading a plug you need to make sure your reading it at the base of the electrode. An idea mixture at the base of the electrode should be about the color of cardboard. Odds are on the street it will always be black. To make sure it's tuned right for the track put in a set of new plugs and run it full throttle. Shut it down and read the plugs after a full out pass. If your just driving it on the street get it where you think it looks good and then put in a new set of plugs. If it's running Idealy on a new engine there shouldn't be any major change in the color or condition of the plug. My plugs are a little black around the base and in the buttom but the electrode still looks new. This is with daily street use. Also make sure you don't have any speckles on the porcelain (preignition)

 

[331 stang91]

Thanks

 

[HISSIN50]

Exactly. To be more explicit, one has to make a WOT run and shut it down at WOT and coast to a stop and check the plugs.