<VV> Weired corvair problem number?

[Vairdad@aol.com]

There are so many weired problems can not remember number. anyway had 
backfiring through driver side muffler, plenty of power but did have some hesatation 
on acceleration. replaced carb, no  help, cold adjusted valve, no help, 
rebuilt carb, no help, so thought I would just drive and worry about problem later. 
cruising at about 60 mph backfiring stopped car ran great.        what do you 
think problem was?
Corvair Driver
Garland