Black smoke coming out of new pipe...jetting ?

[660r2a400ex]

does this mean i am running to rich or to lean? go smaller or bigger on my jets, starts great, idles great, sputters at low rpms, is awesome on 3,000-10,300 rpms. help me please, also i broke my header studs while tightening them, damn that sucks.

[Natertot426ex]

after running it check your plug. if it is white you are too lean. if it is black you are too rich. Did you go from a stock system to After Market or from AM to AM?

[MichaelS693]

to rich in your jetting

[jonc623]

yep rich drop 2 sizes and check plug