I have my BCDD plugged at all the vacuum ports. It isn't fully removed and replaced by a block off plate at the throttle body. I'm using a bare bones '77 manifold, again, on a federal model '80 ZX. This weekend, or most likely today after work, I am going to look into experimenting with how to hook it back up, and see if it's ability to change manifold vacuum changes anything as far as smoke goes. Driving it to work again, with timing down, it seems to be producing the best results I've had since I got it running. Minimal smoke as far as I can tell. Perhaps I can eliminate it completely. Sent from my Coolpad 3310A using Tapatalk