Originally Posted by pinks666
I have a Mito Fourleaf.
I am looking to move onto exhaust mods just to get a lil more sound out and improve the flow and free up some more power. I have already fitted a performance filter with awesome results.
I recently put the car up on a lift to look at what i am working with. I was a lil stumped when i saw the exhaust arrangment and thats why i am asking for help. The car has a cat directly out of the turbo charger. then its a straight pipe 50mm to the back box no other silencers or cats what so ever.
So can i remove the rear silencer without making the car sound like a racing car and still be driveable day to day. The silencer is very small about 300mmx80mm.... I dont want to fiddle with the cat as yet because it would mean getting a custom made down pipe and a lot of parts being removed to just get to the cat.
A Monza or a BTB exhaust system with a bypass valve is bypassing the back box. BTB have proven claims whilst the Monza has been brought into question. Some jam open the bypass valve on the short lived Monzas and it has had no side effects. I've yet to see a bypass setup like this for the MiTo. Some seem to think that a TUV approved exhaust setup makes it road legal but in fact a TUV means that it produces no more power than OEM. So a genuine performance exhaust with real gains cannot be TUV approved. TUV Approval is only required for Germany. 'Here' you would have to watch regulations on noise which is 74 decibels. If one wanted to improved the bhp output on a turbo charged engine going the 'exhaust' route would be more preferable than running more boost given the impact on the gearbox and the turbos (in particular the T-jets with the IHI variants).
So in summary if I wanted the extra bhp I would be tempted to get a custom made back exhaust setup without a back box with 2 single exits either side of the diffuser. If you were looking for a brand name it might be worthwhile contacting BTB. They were offering a stainless steel set-up with a bypass for around a grand on a A500. They would need numbers to commission a similar set-up for the MiTo.
Transport noise pollution : Directgov - Travel and transport
Monza numbers provided by Grajo on the FF...
Moving vehicle 74db
Speed stabilized before acceleration 50db
Stationery vehicle 88db
Taken at 4125rpm apparently
On a side note - which performance filter did you fit for the awesome results ?