What ecu are you running? Is it chipped? Black smoke is definitely from running rich...if it was oil it would be a bluish smoke. My roomate was puffing black smoke in his GSR running the heavily fuel rich mugen program. A fuel tuning tool like a VAFC would help you out a lot, lean it out when vtec hits, and richen it up in the higher rpms....of course it needs to be tuned on a dyno.