03renntechamg

Hello mbworld,

I have an 03 clk 55 amg and im thinking about purchasing some headers. Im looking to gain a little power without having to re-modify the exhaust to pass emissions. I realize the Kleemann headers and down pipes replace the primary cats but would leaving the secondary cats/resenator be enough to pass smog in CA?

Im assuming they would fail visual but at my smog shop that would not be a problem. Im concerned with them passing the sniffer.

Any thoughts or suggestions will be greatly appreciated.

Thanks

Kevwood

They aren't SMOG certified but if you've got a shop who looks the other way then you're doing okay. I don't see any reason why you wont pass the sniff with the secondaries in place - I'm being told here that a set of 200 cell high flows are more than enough to pass the test, another guy told me 100's will pass...?

03renntechamg

Now are the 200 or 100 cell cats in addition to the secondaries or are the secondaries enough to pass emissions alone? Also, will i still experience gains with the stock header back exhaust system?

I realize this is not the optimal performance setup, I just want to keep her as queit as possible.

Klinh

Everyone that i know with header got issue with check engine light come on related to the header. For some, the only way to fix the issue is by turning of the sensor. This is an issue when smog check, you will get an "system not ready" status and fail. The only way to get the "system ready" status is by turning on the sensor but then you might get the check engine again and will fail the test.

Kevwood

I only have one set of cats, the primaries are now in the secondaries location because of the Kleemann headers & downpipes.

novae500

If you get kleemann headers or pretty much any other headers that delete the primary cats, you will need to get a tune to "turn off the rear o2s", but also need to make sure that its still "ready mode"

togaclk55

I think as long as you have 1 set of cats on your car you will be fine

BRIZZOK84

I would also think if you have cats on the car it should be good to pass. The car will throw a code for the deleting cats but a tune can turn it off. Let us know what you end up doing!!!