[davee90]

hello all,

When i fitted my stainless exhaust a while back i gut open and gutted the cat, i did this because i couldnt find a de cat pipe anywhere!
i have now noticed a company on ebay selling them,

my questions is apart from a nice bit of stainless compared to a cut and gutted cat, will there be any differnce.
i mean i assume that with a de cat pipe it would let the exhaust gases run smoother.
but will there be any diiference in sound? id assume even though its hallow, a large empty space would either mask the sound or enhance it compared to a stainless tube.

any thoughts as im doing some work on my car soon so could do this also.

 

[maxoutput]

Probably to try and fool the MOT inspector, I imagine it will fail the emissions anyway unless this is a track only car then it makes no odds obviously

 

[davee90]

This is not a track car, its a fully legal road car and hasn't had a cat for 3 years.
Never failed or advised.

 

[payno]

If you fit a decat it will then be obvious to the MOT inspector and he will fail it

 

[LondonE63]

It's emission based. If it still hits targets within its year then it's ok. I've had straight through exhausts fitted to other cars (not a BMW) and no issues. I would check with the seller/manufacturer that's the case first

 

[davee90]

Ok, well I'm not getting into the rule and regs of mots of diesels and cats.

So does anyone have an answer to my original question?

 

[payno]

there would be a minimal benefit as diesel doesn't have a fast exhaust flow rate
why didn't you weld a strait baffle or just a piece of exhaust pipe in side when you gutted it ?

 

[davee90]

It was a quick and easy cut and gut as a temporary measure until I found a decat.
But it has held its self well and is lasting so I don't know wether it would be beneficial in anyway to justify spending £200.

 

[keith M5]

I removed the cat from my e46 330d, passed two MOTs like that as it wasn't a requirement for a diesel to have a cat (it was an '04). Have to say it made no difference to the performance, economy or the way the engine ran what so ever, so I replaced it.

I have read in other threads that the sky will land on your head, lots of people will die and the authorities will seize your car, crush it and fine you thousands of pounds if you remove a diesel cat or DPF, so based on that advice it's probably best not to touch it at all.

 

[sayekm]

I have read in other threads that the sky will land on your head, lots of people will die and the authorities will seize your car, crush it and fine you thousands of pounds if you remove a diesel cat or DPF.

:hihi