If it idles rough then turn the screw in.
what mods have you done to the IP?from what you say (and that's not much) you need to index the throttle shaft, then adjust the residual and idle screws again.
...BTW your Bieber avatar is awesome.-Malone
I would find out who REBUILT it. It might have been ematia, I got one of his and it ran worse after the rebuild and was missing a few peices. I would use the max fuel screw to adjust your power/smoke. When you have it barely smoking under load then go back and set the idle. That is what I did and I am not a pump guru....If in complete doubt go to the vendors section see a man named GILES and get out your check book.
Did you take it off the car? Cause it sounds like the timing may be retarded as well.