F-Body Europe

One question: When I find all these adverts for longtube headers, where does the cat on the drivers side go? I guess it must move further back.
So far I have not come across aftermarket headers which are called short or medium tube headers.

Does somebody have a picture?

The problem in Germany is to keep the car road legal (TÃœV and emissions).

Long tubes will move the cat slightly rearward, but there are some companies out there that make mid-length headers. MAC is one of them. Don't get shorties, whatever you do, because they're a waste of money! They might look nice, but give you virtually zero performance increases.

Just a bit of useless info:
If you want performance then the longer headers are the way to go.
However, to get the cat to work at its best you want it to sit as close to the exhaust port as possible. If you move the cat backwards it takes longer to reach the ideal temperature after startup. So if your car is marginal, make sure the exhaust is nice and hot before the TÃœV guy sticks his sniffer up your pipe.

Problem with that is, 1/3 of the emission testing is done on the cold motor ... e.g., I got my Toyota into a better emission class by adding a part to the motor that raises the cold motor RPMs in order to heat up faster ... kind of stupid that something that only matters for some 2-3minutes per trip is valued that much ... german laws s@ck ...

Seems 2slow knows a thing or two about engines!
The things with cat close to the engine I have heard also.

But one thing has striked me for a long time: Will there be any change in emission, when I go for ported heads, different cam and different headers (supposed the cat heats up quick enough)?
More Power means more CO2, but will the percentage of CO, NOx etc increase?
Somehow the big Brabus V12, Ferrari engines etc also achieve Euro4.

To bring it to the point: Will the TUEV find out at the emission check???

With a sniffer up your cars ass and depending on the camshaft yes you will flunk with flying colors. You may pass the visual depending on how bright the guy is . But if the car is thumping as it is coming in the door you don't have a chance .

What they do (and it is quite legal) is to pump fresh air into the exhaust system. The exscuse is to supply extra oxygen to burn away any left-over fuel particles etc. etc., but what it also do is to thin down the exhaust gas.
You are not worried about the total quantity of CO, CO2 or NOX, what matters is the percentage of bad molecules in the exhaust gas. Therefore the displacement of the engine does not matter.
On the other hand we only have this planet to live on, so do not mess it up.

You are right, but it really seems like some of the "higher ups" don't want anyone to have any fun.

I certainly agree. The Fbody is definetely not environmental friendly, but I will stay within the legal emission limits.
I do not agree with those people, who take out the cat, only because they do not need to worry about TUEV.