Morning all! Hope you had good weekends! I recently bought a 2002 Focus ST170.
The exhaust was rattling like crazy so i swapped out for a mongoose cat-back and toyo sports manifold and decat. However now it’s worse and sounds like an engine noise, the engine was quite tappy before and still is but runs and drives mint. I haven’t ran it on the road at all since fitting the new manifold because of the rattle getting a lot worse.

any help would be greatly appreciated, I will post a video later on today for anyone interested.
Kind regards,
Jamie Allan.