my 1981 Firebird failed smog cuz of extremely high HC and CO. I have a rebuilt carb

[PontiacFirebird]

in. what can be wrong? i have a rebuilt carburator in it (maybe a dud?). my engine was also rebuilt. I have a new diverter valve, catalytic converter, spark plugs, alternator, and egr. my HC level on the first smog was 163 at 15mph, but on this third smog test it was at 336. HC level at 25mph went from 169 to 359 by the third smog test. As far as the CO levels, on the first smog it was 4.23 at 15mph, and 4.50 at 25mph. On the third smog test the CO levels were at 6.66 at 15mph and 7.56 at 25mph. So, my car is now considered a gross polluter and its failing smog specifically because of the HC and CO levels.

 

[Goatman]

Sounds like you need to take it in and have it tuned by a shop that specializes in emission tuning (I am assuming you are in a state that has emissions) so there must be shops that specialize near by..
tuning for emissions can be a frustrating deal and most people don't know how to do it properly so find a shop that does it will save you in the long run ..