i am try to determine if i am running rich or lean. if i remember right either way will put off a pretty strong odor from the exhaust. my question is, how to distinguish between the two odors? i have a slightly modified 350 (small rv cam, bored .30 over), but i'm running a qjet from a 305. i've gone into the carb 3 times now, trying to get it right, i would like to get it right this time. thanks in advance.