darrens99formul

I am new to the high performance world of lt1/ls1 so please bare with me. I have started my mods on a 99 formula with a dynomouth exhaust setup. I am also purchasing some bolt-ons such as SSRA, TSP lid, holley air filter & bellows. I am avoiding the MAF for the time being because I read in several posts it's a waste of money unless you plan to go beyond 450 rwhp. Correct me if I am wrong on that.

I see that headers/y-pipe/HF cats are on just about everyones car or x-mas list. I am a little hesitant in this area because I read that there is a federal law that says it is illegal to replace or relocate the factory cat on any street vehicle. Now again correct me if I am wrong but doesn't that make LT headers Illegal in all 50 states because it requires at the very least relocating the factory cat if not removing/replacing?

I am by no means a model citizen but I do need to use this car as a daily driver and I need to be able to pass emissions. I am in the Chicago, Illinois area and want to know how I can have headers and still pass emmisions testing?

Just wondering if there is some secret I need to be let in on or if I have my information wrong.

SSCamaro99_3

Most techs will only look for cats. 99% don't know where the stock location is or care.

darrens99formul

Thanks. Then I should be ok as long as I keep a cat/s in the exhaust setup somewhere.

WoHoo I have just added headers to me early X-mas list!

jd13

You'll be fine as far as emissions goes if you use cats when you get headers. I've never heard of anyone having a problem that way.

Constrictor98TA

Darren, yes, you are correct. It is a Federal violation to relocate or mess with the stock placement of any emissions control device.

So, yes, every single person with mid or long tube headers regardless if they have cats or not is in violation of this law.

The good thing is, most inspection places do not know the stock location of the cats on our cars. As long as the install looks clean and you pass all the other tests, you should be fine.

I live in IL also, and I have had many cars get tested (my Honda got tested just this past weekend) and they never so much as looked under the hood or under the car. I wouldn't worry about it too much.

Lastly, if you are looking for a good shop to install your LT headers, the guy that did mine did a great job and I'd highly recommend him. He is in the far south suburbs, so if you're anywhere near there and are interested, let me know through email or PM.

Black6SpdTA

its illegal to move the cats but why? it still does its job.

Eric L

Cats work best when hot. They are hottest close to the engine. hence the law. If there are other reasons they'll add to it.