Audi S5 B9 Instalation of 034 Stainless Steel Racing Catalyst and sound comparacent 

It was difficult but we still win. Catalyst from 034 installed and we are happy. it does the job as it should, please watch the video and learn from my mistakes instead of doing yours ;)
enjoy the video and do not forget to like and subscribe for more videos ;)
in the video link below you will be able to see in description all upgrades video guides i am planning to do.
• Audi S5 B9 full Dyno 0...