Advance your timing to 15. 5-16deg (~1. 5mm). The smoke screw wont affect this, as the governor is at or near minimum fuel flow- read the sticky and the link. I have mine backed out, but I can still hit 22psi w/o the AFC even being hooked up.
The smoke screw affects the STARTING POINT of the tapered pin travel (or fuel curve- how far reaeward the guide pin is at full throttle); the starwheel affects the RATE of increase, more tension on the spring, slower fuelling increase, and vice versa.
Change fuel filter and check LP pressure. I forget the exact spec off hand, but it is easy to check- the 10mm bolt head you loosen to bleed the filter is a 1/8NPT thread, or real close to it.
Injectors not up to par will make blue, grey, or white smoke, depeding on what it is and how bad it is.
Check your air filter- this will NORMALLY make for grey to black smoke, but it could still be complicating things.
Daniel