Welcome to Just Commodores, a site specifically designed for all people who share the same passion as yourself.

New Posts Contact us

Just Commodores Forum Community

It takes just a moment to join our fantastic community


100 or 200 cell cats


New Member
May 20, 2020
Reaction score
Members Ride
Ve Commodore
G'day. I'm sure that this has been done a lot. I've searched and found similar topics. But what I'm wanting to know is what you guys are running. I'm looking at getting some 4 into one headers for my LS1. Ideally I want 200 cell cats as that's what you need to have legally. But I can only find systems that come with 100 cell cats. And the bolt on cats by themselves are also only 100 cell (as well as being about 600 bucks).

Is everyone just using the 100 cell cats, or have you gone to exhaust shops and had them weld some up for you? Trying to save money where possible and am looking at some cheap used headers at the moment. But looking at prices I can get new ones with cats for less than the used ones and a set of cats online. No idea what a shop would charge, or how to even get the car there without cats on it. Assuming headers won't bolt up to the standard cats.

The alternative that I'm looking at are a set of xforce headers with cats for around 900 bucks. Again. Sorry if this is a common topics. The other posts only mention that 100 cells are not legal, but don't have anything there about where to get 200 cells done.


Exhaust Guru
Aug 18, 2006
Reaction score
Bunbury, WA
Members Ride
Strange Rover
200 cell are the highest flowing Euro 4 compliant cats on the market. 100 cell are not for road use, even though everyone sells them. As far as I know, MagnaFlow are the only ones that make the Euro 4 200 cell cat.

Manta will make a set of 200 cell cats if you ask for them, but they aren't cheap. Most other suppliers won't, they only use 100 cell as they are cheap.

The factory cats will not bolt up to long tube 4-1's, there are a couple of manufacturers that make headers and cats that bolt up to the factory cat back. But again, using 100 cell cats.

You will be spending around $1600 - $2000 for a set of 4-1's and 200 cell Euro 4 cats. (new).