Hey there Oppo, long time no see. It’s about that time of year again when I’ll be getting the Corvette out of storage and on the road again. It’ll be going to the shop to get the valve seals and a few other niggling things done to get it back in tip top running shape. Long story short, I was thinking about possibly getting a new Borla Front Y-pipe, since the one on there is stock, but I have a high flow cat and a Borla cat back system after that. Now, obviously, the original system has pre cats, and I would be looking to get rid of them with the new Borla one.

Now here’s my question: are shops allowed to take off pre-cats? I know that they cannot remove the main cat, but I’m not sure on pre cats. Now, keep in mind, I still have a main cat, so I am not just completely ditching my emissions stuff. It is just that the stock Y-pipe is very restrictive, and I’m sure those pre cats are pretty shitty. So, what do you think?

TL;DR: Can shops take of a front y pipe with pre cats and replace it with one that has no pre cats?