So my Prelude '98-'99 2.0 133PS gives a high CO value, that means that I cannot pass the "General Car inspection". First we thought that it was the Lambda, which wasn't. It is ok. So, basically it leaves us to the catalyst.
I am on the market for a catalyst, but on my way, I bumped into a question which is:
If I had to choose for a catalyst, what size does the diameter of the pipe be? I mean, I found here: **Link**
, is it any good?