Exhausts For Dummies

[brad]

I've been looking into a custom exhaust system for my B7 RS4. I've read a few sites, but still don't have my head around all the options you can get and what they mean. Can anyone provide a brief rundown on these topics?

- Cat backs?
- Resonated vs. Non Resonated?
- Downpipes?
- High flow catalysts?
- Are there any other options other than the above?
- How do all these things they deliver more power / torque?
- Are there custom exhaust systems which honour the sport button on the RS4? (ie more noise + more power? when pressed, more sedate when not)
- It seems like Milltek are the only guys making systems which have the same oval rear pipes, is anyone else doing these?


Any informed feedback is appreciated.

Thanks.