Ok now I need some help..

Ok so I got by with searching the forums for help but now I need to be specific. Long story short I got a new weber for mY 92 b2200 it is a 32/36 dgev I got everything done (no I don't have any vacuum leaks) and it runs good besides the fact that when I kill it sometimes it spits and spudders and backfires.. Basically I think it running rich or something.. I have never tuned a carb before but I got it running decent. Trying to figure out why it spits and spudders when I turn the key off??? Any ideas?

Sounds like it's dieseling or having run-on. There's no electric solenoid valve on these to shut off the fuel immediately when the key is switched off. I've found that if my own Weber is set to idle too high (over 1000 rpm) or too rich then mine can diesel also.