GoremanX
Veteran Member
A couple years ago, I invested a LOT of money in a custom 3" stainless steel exhaust system for my 2001 Audi A4 1.8T. A large chunk of that money was spent on a 3" downpipe with a high flow cat.
If at all possible, I'd like to retain that exhaust system. It's treated me very well over the years, it looks fantastic and it sounds awesome... and as I said, it cost a LOT of money.
But obviously it's got a 3-way cat since it was designed for a gas engine. How will a 3-way cat hold up to a modern diesel engine and ultra low sulfur diesel?
edit: to clarify, in Vermont, there's an annual safety and emissions inspection. If an engine had a cat from the factory, then it must be present to pass inspection. I see a cat on the Passat donor vehicle. Vermont does not actually measure emissions at the tailpipe, so its efficiency doesn't really concern me in that regard. But it would be nice to be compliant in spirit without causing mechanical issues.
If at all possible, I'd like to retain that exhaust system. It's treated me very well over the years, it looks fantastic and it sounds awesome... and as I said, it cost a LOT of money.
But obviously it's got a 3-way cat since it was designed for a gas engine. How will a 3-way cat hold up to a modern diesel engine and ultra low sulfur diesel?
edit: to clarify, in Vermont, there's an annual safety and emissions inspection. If an engine had a cat from the factory, then it must be present to pass inspection. I see a cat on the Passat donor vehicle. Vermont does not actually measure emissions at the tailpipe, so its efficiency doesn't really concern me in that regard. But it would be nice to be compliant in spirit without causing mechanical issues.
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