lately, i've noticed the car backfires some under hard acceleration in between shifts... and there has been some black smoke coming from the back... what could be the culprit... i'm just guessin its runnin rich?
I would say that you are definetly running rich. And as far as the backfiring goes, does that change if you use premium fuel? I am thinking that with all of that fuel in your cylinders that it could be detnation. If you have access to a scan tool then you should look to see what your o2 sensors are doing. You could also do this yourself with a multimeter. Then check your basic things like Fuel Pressure. Double check your timing also
Good Luck