My first car was a 1980 Rabbit. I bought it in 1984. I had it and got it smogged every two years and after about 8 years the smog tech told me the car didn't have a cat, in its place was a "test pipe". This is how I purchased the car. Funny thing is that he was the same tech that passed me the years before. So I went to to the junk yard and purchased a cat (this wouldn't be possible today).
So I still have the test pipe and I also have a 1984 gti rabbit, same flanges and size.
Was curious if I would gain an benefits of removing the cat. And if so what would they be?
I remember years ago reading something about CIS depends on the backpressure of the cat to work properly? Is this so?