[FC] Hot Running Issue

[ROBERT WILSON]

Anybody have experience with this issue? 
  
Sometimes on hot days (about 90 in MI today) during a longer drive in my Corvair, it will start backfiring and running sluggishly when I try to give it gas (accelerate) at speed (say 50 MPH).  Today I carefully backed off on the gas and it sort of cleared up.  When it cools off it seems to be fine.  
  
I also have the hot starting problem that plagues a lot of our Corvairs. 
  
Does this sound like I need a carburetor rebuild? Or maybe it is related to flooding somehow due to running hot? 
  
Thanks, 
  
Scott