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Soot on exhaust pipe means ?

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Does this mean that I am rich or lean? I've got the DJ kit and 3x3 with modified stock exhaust. Bigger/smaller jets, fuel screw, etc. will fix it - or just the nature of the beast?

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Not much. Read the porcelin of the plug if you want to know if it is jetted correctly.

Your looking for a nice even extremely light tanning of the porcelin. If you see little tiny black pin point specs...you are getting preignition or detonation. IF you have those increase your octane.

If it is pure black...you are too rich. If it is pure white you are too lean. If it is pure white and the side elctrode is melted off...you are extremely lean.

If the plug is smashed...you probably just dropped a valve and have grenaded the motor. :banghead:

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Not much. Read the porcelin of the plug if you want to know if it is jetted correctly.

Your looking for a nice even extremely light tanning of the porcelin. If you see little tiny black pin point specs...you are getting preignition or detonation. IF you have those increase your octane.

If it is pure black...you are too rich. If it is pure white you are too lean. If it is pure white and the side elctrode is melted off...you are extremely lean.

If the plug is smashed...you probably just dropped a valve and have grenaded the motor. :banghead:

i'm kinda confused here.... had my plug out yesterday when checking the valves...

the threaded end of the plug was black, what's that mean? and if it's too rich/lean, could you be ever so kind as to explain what i need to do to fix it?

thanks.....

oh yeah, by the way, valve adjustment/cs nut fix went smooth as buttah..... valves were still in spec, so no problems on that end

and the only dumb-dumb thing i did was forget to drain the coolant before taking the case off....DOH!..... well, that and drop a socket in in the oil pan... DOH-DEE-DOH-DOH!!

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I should point out that this is only rule of thumb. To get it really right requires a dyno and a lambda sensor.

Don't care what the threaded end looks like...only the porcelin. Generally speaking a black plug needs a smaller jet and a white one needs a larger one. Of course needle position could play a role here.

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ah, it's running fine the way it is..... i'll just enjoy it "as is" right now.... next time i'm changing the plug i'll make a note of the coloration and tinker accordingly

thanks for the info, fellas

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