Having an almost standard polo it's time to change the exhaust (cat-back) because both silencers in the boxes are broken so they start to make noise...
I'll definatelly use inox pipes and boxes with inox welding...
Also, i'm going to make 2 boxes to keep the noise down...
My question is what's the most efficient bore that the exhaust must have (from midbox to backbox)
Thank you for your time, Alex...