18 hours ago, rcb280z said:

I can just make out a raw fuel smell when coasting now. I didn't have this before. That extra air entering the intake is no longer there while coasting. I would have that with a working bcdd.

Yup. that's the exact situation where the BCDD is supposed to help, not steady state on a dyno. The BCDD will also help reduce the amount of oil pulled past the rings and valve seals when the cylinder vacuum goes up when you let off the gas and the intake manifold vacuum spikes. Especially on a worn engine.

On my first Z with it's worn out engine, I used to get a terrible eye-burning blast when I completely let off the gas at very high RPMs. I believe I have a much better understanding of the system now, and looking back, I don't think my BCDD was doing anything. That extra rich mixture (too rich to burn), combined with a whole bunch of oil getting pulled past worn surfaces produced a bird dropping cloud of unburned HC's.

I was a new work force entrant then just trying to get to work. Now I'm a tree hugger.

29 minutes ago, Captain Obvious said:

I was a new work force entrant then just trying to get to work. Now I'm a tree hugger.

Exact reason why I'm replacing mine.