I have the Revo Chip in my 04 1.8T Quattro. Now I'm planning to get a catback exhaust and
replacing my cat with a high-flow cat too.

Question is, how will the Stage 1 chip react since it wasn't designed to work with a full exhaust?

 

With just the CAT back exhaust you'll have no problem. If you get a high flow CAT then you might throw a CEL, that is what the Stage II software would fix. I suggest relogging the car after any adjustments to make sure the fuel, air, and boost is all in line.

Cheers!

 

hey chef didi you have any problems with loosing boost on your stage 2 revo chip?[&o]