I didn't figure on chiming in on this subject cause I didn't figure I had anything to add. I've heard of air bleed carbs but didn't really understand how they worked. Thanks Allen for your visual that helps me picture it. If I understand the concept right it gives the intake more air when the throttle is nearly closed & would otherwise be sucking even more fuel. W/O the air bleed there would be that much more vacuum to pull fuel in. CHP if I recall my Volvo 140 series properly, SU's had the unscrew lid and yes I had the oil can in the firewall to fill it. The Stromberg's had a rubber diaphragm. Has anyone done anything like that with the jet controlled by the engine vacuum? My boss says oh that would be easy. But I think the hole sizes might not scale as expected.
Art