[brcidd]

The increased sound (and volume of air flow) you hear/feel while rounding corners is most likely due to a vacuum leak. The recirc air door is driven by vacuum, and when vacuum is not adequate, the door will close and the air path is more restricted and longer as it sucks in outside air instead of the shortcut to inside air. You are hearing the increase and decrease of air volume as the door opens and closes. Also, the mode doors will be affected, and air flow can be diverted to defrost, as vacuum comes and goes. Find and fix vacuum lines- most likely at underhood vacuum reservoir or at intake manifold source connection. - look for brittle heat baked black plastic and crumbly rubber connections on intake manifold right behind a/c compressor. Hard to get to, but you can feel the way around....

Yes, your blower relay is highly suspect, the burn marks you saw on the terminal at the blower motor are probably also present internal to the relay contacts. There might even be melted plug/terminal right at the relay as you saw on the blower motor. A quick inspection would be in order. Astros are notorious for blower motor wiring overheating at the connections issues. Napa sells the new wiring harnesses that can be spliced in to replaced the brittle, melted terminals you are . likely to encounter. The relay is built into the resistor module, so since you replaced that, the wiring terminals are the next thing I'd consider.