[CaptainAhab]

I am nearly ready to swap out the Solex Cisac for the Weber DMTL, and I am reasonably content that I know what I need to except for one thing.

On the Solex there is a large bore rubber pipe leading from the underside of the plenum chamber, controlled by a solenoid, that runs off under the car beside the fuel flow and return from the tank. I have scoured a few books and the net and the best I can come up with is that it might be a float bowl vent. Not sure why a vent for fumes would go down rather than up unless it is positively drawn out by something.

Anyone know for sure what this pipe is and where it goes?

Also, a pic of the new setup, because shiny.