Fitted a resonated scorpion cat back to my mk7 ST180. Brand new exhaust and it bangs/knocks like hell. It's been adjusted twice by the same garage and I decided to powerflex polybush the backbox, which helped slightly but still knocked. I polybushed the rest of the hangars and had it adjusted completely from front to back again and although it's a lot better; still knocks/bangs. It sounds like the exhaust is hitting either the underside of the body or something else. It's fine over speed bumps and pulling off kerbs, but uneven roads and potholes still make it bang. Can't figure out how to solve it completely?

Hi mate, 

seen no one has replied to this, I have a Ford Fiesta Mk8 and have had the car for over a month now. I have a Custom Quad Scorpion tip exhaust with a GPF delete. Which also bangs and makes an awful noise in the cabin. From the muffler hitting the heat shield and then sending a vibration through the whole frame of the car. I’ve also took it to several garages and they’ve all said the same thing that the exhaust is too heavy and not designed very well. Hence why I’m going to be changing it to a Milltek, luckily the previous owner made the bad decision to purchase the Scorpion Exhaust. 

 

8 hours ago, LukeWoodST200 said:

 I’ve also took it to several garages and they’ve all said the same thing that the exhaust is too heavy and not designed very well. 

Heard a similar story some time ago but it was on an Audi and the SS exhaust was too heavy and banged the chassis.

Being heavy would result in the exhaust being forced downwards, then the weight of it being flirted back up, hitting the bodywork, I'd look to see where it's hitting the underside and make a further bracket/hanger and attach another bush.