1969 camaro ss 396 big block
 

1969 camaro pours gas out of exhaust pipe and goes through a full tank in 30 miles.
Any answers?

Carb leaking and/or float set too high.

Sounds like carb rebuild time, better drop the oil and filter there's probably gas in there too and that could kill your engine.

And I wouldnt run it till you get it fixed .It will kill the engine ,Of which can become very expensive.

Holly washed down cyl walls Batman....absolutely stop driving until you get the carb fixed....and change the oil