Yes and it will run like crap. One of the easiest ways to check is to blow a hole in the pipe between the manifold and converter. Then start the car and see if exhaust gases are blowing hard. If not, you can weld the hole shut with the torch.
68 Coupe, 350 w/ Edelbrock Performer RPM heads, cam, intake, 700R4, Dave's small body HEI
if you have developed a whooshing sound form your exhaust when you rev the engine,it's probably a clogged converter.don't know where s.a.is but you could install a straight through "test pipe"to replace the cat to see if it helps.