CARBON DEPOSITS in your combustion chamber can cause the pinging noise as well, what happens... the carbon gets built up in your combustion chamber and then everytime your ignition fires in the cylinder it combusts (of coarse, I hope) sometimes the amount carbon that is built up in the combustion chamber can stay lit (like charocoal) and will act as spark firing on the wrong stroke, however its not as volital as it would be coming from your iginition. The vulcan 3.0 was bad about this, I would try to clean your combustion chambers by buying some fuel treatment, getting your engine good and hot, remove the vaccum hose from your booster, stick the hose in your bottle of gas treatment bottle then start to rev the engine. Depending on how dirty your combustion chamber will determine how much smoke you blow out of the exhaust. Its good to keep the RPM's between like 1200 to about 4000 and periodically tach it out to ensure that you have successfully burn off any residual gas treatment.

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98 Ranger, Bagged 2600's in the front, 2500's in the rear. 3 Gal tank. DJM Upper and Lower control arms. 2 Thomas Compressors (garbage). 4 linked rear with C-notch. All (except cab) fiberglass. Custom Tribal Paint (soon to be Sunburst/burnt Orange).
Coming soon - 405HP 4.6L (SOHC), 4R70W