I used to own a 2006 Audi A4 but ended up selling it and buying a mustang cobra. I still have the aftermarket testpipe with custom check engine light avoider(defouler) i had welded on for about 80 dollars(including defouler). The testpipe ran me 299.99. uses stock hardware. you can reach me at 248-231-4208 with any questions about the testpipe

RPM HP Gain TQ Gain
2100 19.42HP 48.88TQ
2400 14.02HP 30.70TQ
2600 12.55HP 25.35TQ
2900 13.40HP 24.28TQ
3100 11.24HP 19.05TQ
3400 8.73HP 13.49TQ
3600 10.45HP 15.26TQ
3900 11.47HP 15.43TQ
4100 4.39HP 5.63TQ
4400 8.24HP 9.84TQ
4600 9.12HP 10.34TQ
4900 8.80HP 9.43TQ
5100 10.63HP 10.95TQ
5400 9.68HP 9.42TQ
5600 9.71HP 9.11TQ
5900 8.35HP 7.44TQ
6100 12.22HP 10.50TQ
6400 10.66HP 8.75TQ
6600 15.00HP 11.94TQ
6800 17.45HP 13.49TQ

pipe diameter-back of the turbo with a 2.75" Diameter and transitions to 2.5" D down at the factory downpipe flange.

 

I'm interested (mainly because of the defouler), but there are VMR testpipes going for 69$ right now. Why is this one so much more expensive?