I would have offered you my airbox set up already, but i don't think it'll work. Having owned both, I can tell you that the airbox is different. The 1.8 has the outlet on the front, going out to the turbo inlet pipe. The 2.8 has the outlet on the back, heading back to the throttle body towards the back of the intake manifold. If you want to try it you're more than welcome to it, but I don't think its gonna work.

 

I have the original airbox from a 1.8t a4, and the orignal airbox from a 2.8 1999 passat?
Want either of em?

 

I did more research and the 1.8 airbox definitely doesn't work but I would be interested in the 99 2.8 Passat airbox. That should be a match. Do you have all the ductwork/hardware? If you look at the diagram on the first post I need everything but #19-29. How much do you want for it?

 

Uhm, i have the complete airbox and filter.
As far as the tubing and maf, im using them in my intake setup.
So id need a replacement before i could take those out.

 

I have the complete stock air intake from my 1996 audi a4(2.8L) if you would like we can take care of it over e bay