Should I delete cats?
Burning Brakes
Joined: Jun 2007
Posts: 877
Likes: 142
From: Little Egypt, USA
No smell to bother me on my 07. Smells no worse than any pre cat car, i.e. 1974 and older.
Advantages you will get over cats: less tunnel/floorboard heat, better sound, better flow (the 4 or 5 hp), save $300 to $400 on the cats/rear O2 extensions plus you don't have the hassle of routing the rear O2 wiring. I have no drone and great sound with headers, no cats and the stock exhaust.
I recommend going catless if you want the above advantages. You can always add cats later if you change your mind. As far as violating the federal emissions law, once you install the headers the law is broken cats or no cats.
All the above is of course IMHO.
Advantages you will get over cats: less tunnel/floorboard heat, better sound, better flow (the 4 or 5 hp), save $300 to $400 on the cats/rear O2 extensions plus you don't have the hassle of routing the rear O2 wiring. I have no drone and great sound with headers, no cats and the stock exhaust.
I recommend going catless if you want the above advantages. You can always add cats later if you change your mind. As far as violating the federal emissions law, once you install the headers the law is broken cats or no cats.
All the above is of course IMHO.
Drifting
Joined: Apr 2008
Posts: 1,955
Likes: 22
From: Lehigh Valley Pennsylvania
If you have to pass a sniffer it will most likely fail. There is not much of a HP gain unless you are F/I, which in that application they have been known to clog. I don't know how the high flow cats fair for the sniffer test either that being said.
Melting Slicks
Joined: Apr 2007
Posts: 3,290
Likes: 0
From: Willow Springs IL
If there is any type of "visual" inspection for emissions equipment in your area then you will automatically fail without cats. Even with high flow cats in a long tube header application you will still fail because the cats are no longer in their original factory location. If you have to deal with any of these tests, then you really cannot use any type of aftermarket long tube header. You will most likely not pass a sniff test either without cats. In my area all you need to pass the emissions test is the OBD test. As long as a check engine light code is not present, then you automatically pass. There is no visual or sniff test anymore. I of course still have cats on my car though.
Le Mans Master
Joined: Nov 2004
Posts: 8,718
Likes: 20
From: Dyer IN
Cruise-In IX Veteran
If there is any type of "visual" inspection for emissions equipment in your area then you will automatically fail without cats. Even with high flow cats in a long tube header application you will still fail because the cats are no longer in their original factory location. If you have to deal with any of these tests, then you really cannot use any type of aftermarket long tube header. You will most likely not pass a sniff test either without cats. In my area all you need to pass the emissions test is the OBD test. As long as a check engine light code is not present, then you automatically pass. There is no visual or sniff test anymore. I of course still have cats on my car though.
Burning Brakes
Joined: Jun 2007
Posts: 877
Likes: 142
From: Little Egypt, USA
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