At about 3,000 RPM in first gear you can feel the car fall on it's face and barely gains any speed and at about 5000 RPM black smoke shoots out the back (fuel I'm guessing). It doesn't really happen in other gears but I can tell the car isn't taking off like it should, slow acceleration basically. I'm thinking it could be the fuel pump but I just wanted to see if anyone else hear had an idea. It idles a bit rough too.

 

I'd replace the fuel filter, and if you have a cat, make sure it's not clogged.