Yes, it will fit.but you have to have a rear o2 bung put in for the 2nd sensor....and yes, they have been shown to pull from 9-12 hp... Brad B. Phx AZ '96 200sx SE-R(w/ this 'n' that) '01 Altima GXE LE > Will HS Headers fit My '02 G20 with little or no other work? > Are HS Headers good for some HP gain?