I have a 670 SA on a mild 383. Only major mod is box stock Eddy heads, MP duel plane, stock exhaust manifold, MP "resto" purple shaft cam. Car runs good but very rich at idle. Mixture screws at @ 1/1/4 turns out. Vacume is 14" steady. I took the carb off and looked at the idle/main transfer slots; about half of the slot is exposed. Is this too much? Also, what's the correct way to adjust? The idle screw just barely touches the throttle plate so turning it out (less idle)won't have any effect. I seem to remember something about a "secondary idle screw" but I can't seem to find one on this carb. Your thoughts

Frank,
You might want to check out the thread below. A lot of good info and pictures were posted. It may help your troubleshooting.
Ron

https://board.moparts.org/ubbthreads/show...part=1&vc=1

Thanks. Lots of good info there. I was able to solve the transition slot adjustment.