I'm having similar issues, albeit on a much milder engine combo. So here's a BTT.

Bee4spd, I think Bob (the OP) is at least on the right track now, so the thread could die if you wait for more action there.

Go ahead and describe your setup and the degree to which your exhaust stinks.

Jim

Okey doke. My car is a '70 Super Bee around 3750lbs. with me in it. The engine combo is a 452 with indy s/r heads(no porting). Compression ratio is 9.5:1(low), cam is a solid 268 adv.(239@.050) intake and 274 adv.(247@.050) with 1.6 ratio rockers lifts come out at around .570/.556 before lash, this cam is ground on 108 degree lobes and is in straight up. Carb is a holley 830 annular. My idle doesn't smoke like the original posters does, but definitely gives you the stinging eyes and lungs affect. I've done the wire trick(going to try some thicker stuff after re-reading the calculations above), got the throttle blades set appropriately(less than .040 transfer showing), set the floats(interesting things found whilst doing this, the o-rings on the needle and seats were shreaded, replaced needles and seats). The idle quality has definitely improved, but the stink is still quite debilitating.
One question I had was: is there a point of diminshing returns with just playing with the fuel side of the equation?(ie. if I get to a certain point with the IFR's, will I have to do air bleed work?) Thanks in advance,

Brian