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If i was to get a custom exhaust system that included a decat, i assume this would also remove the DPF as well if i got the pipe made from the manifold?

If so, can the car be driven without the DPF without a map? Or would i have to tell the ECU that the DPF has gone?
 

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If i was to get a custom exhaust system that included a decat, i assume this would also remove the DPF as well if i got the pipe made from the manifold?

If so, can the car be driven without the DPF without a map? Or would i have to tell the ECU that the DPF has gone?

Yes, you need a remap that deals with the DPF delete before you can remove it...
Otherwise your dash will light up like a Xmas tree after a little while...:lol:

If I can make a suggestion, you'd be better off with a decat pipe. This allows you to pop it back on without having to replace the whole system. I'd be surprised if you'd gain much with a dedicated decat system over a straight through system with a decat pipe...

My car has the Alfatune straight through stainless system with a decat pipe and works very nicely indeed! :thumbs:
 

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Just had my decat pipe fitted today (already have dpf removal/remap/full stainless steel straight through exhaust.)

The way the car revs now is just unreal. The turbo spools up so quickly and throttle response is second to none. Very happy chappy! Absolutely loving the sound too! By far the best diesel car I have ever heard. Will try and record a video
 

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Just had my decat pipe fitted today (already have dpf removal/remap/full stainless steel straight through exhaust.)

The way the car revs now is just unreal. The turbo spools up so quickly and throttle response is second to none. Very happy chappy! Absolutely loving the sound too! By far the best diesel car I have ever heard. Will try and record a video
I really do need to stop reading these threads and putting this naughty thoughts in my head. I was happy with remap and DPF delete now I realise that I need decat and full exhaust now :(
 

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I really do need to stop reading these threads and putting this naughty thoughts in my head. I was happy with remap and DPF delete now I realise that I need decat and full exhaust now :(
I was exactly the same :S.... I think I am done now tho! :) It goes and sounds as it should. There is so much more you can do but it starts getting complicated.....

When I post a video of how it sounds, I suggest you don't watch it. It's quite infectious lol
 

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So DPF delete has to happen before decat exhaust system?
There's not much point in a DECAT unless the DPF has been deleted. All the decat does is improve exhaust flow...only for the flow to be stopped dead in its track inside the DPF...

My advice is to save up and do it properly... get a DPF/EGR delete remap, full stainless straight through exhaust system and decat pipe (e.g. Alfatune).

You won't be dissapointed...
:thumbs:
 

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Just had my decat pipe fitted today (already have dpf removal/remap/full stainless steel straight through exhaust.)

The way the car revs now is just unreal. The turbo spools up so quickly and throttle response is second to none. Very happy chappy! Absolutely loving the sound too! By far the best diesel car I have ever heard. Will try and record a video
My car will be going back on the dyno later this week(Friday). Hopefully I'll be able to record some decent sound/video footage and post it on my Skunk Works thread... :cool:
 

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Not sure about decat pipes etc so just exscuse my ignorance but what happens at MOT time?

Reason i ask is...

I had my MOT last week and the examiner was concerned the DPF was missing, which he originally thought was the Cat that was missing as he said that the Cat needed to be present for the MOT, while after checking with VOSA the DPF did not?
 

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Discussion Starter #10
There's not much point in a DECAT unless the DPF has been deleted. All the decat does is improve exhaust flow...only for the flow to be stopped dead in its track inside the DPF...

My advice is to save up and do it properly... get a DPF/EGR delete remap, full stainless straight through exhaust system and decat pipe (e.g. Alfatune).

You won't be dissapointed...
:thumbs:
I was thinking that the exhaust system would incorporate the DPF deletion

Not sure about decat pipes etc so just exscuse my ignorance but what happens at MOT time?

Reason i ask is...

I had my MOT last week and the examiner was concerned the DPF was missing, which he originally thought was the Cat that was missing as he said that the Cat needed to be present for the MOT, while after checking with VOSA the DPF did not?
Diesel's dont need a Cat to pass MOT
 

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Unfortunately the MOT Rules are changing in January and if a cat was fitted at new then it is required to pass the MOT. as per another post the question of if you smash out the innerds of the Cat then i can't see how it will fail as there is no Cat test but the box will need to be present.

As per the post above though, thats my concern about removing a DPF. Even under the new rules they don't mention the DPF therefore doesn't need to be fitted but how many MOT Testers sill know the difference between a Cat and DPF and therefore fail it anyway!
 

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Unfortunately the MOT Rules are changing in January and if a cat was fitted at new then it is required to pass the MOT. as per another post the question of if you smash out the innerds of the Cat then i can't see how it will fail as there is no Cat test but the box will need to be present.

As per the post above though, thats my concern about removing a DPF. Even under the new rules they don't mention the DPF therefore doesn't need to be fitted but how many MOT Testers sill know the difference between a Cat and DPF and therefore fail it anyway!
I have mentioned this before somewhere. Mot testers are not allowed to remove anything when running a test. On the Brera/159 2.4 engine, if you can see the cat just by looking down on the engine bay then you have better eye sight than me. There is no way they can tell if it's there or not without jacking the car up and removing the under tray. As for dpf, any car from 2008 onwards if it had a dpf from new and has now been removed is an automatic fail under the new rules. Fortunately my car is a 2007 plate.
 

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Discussion Starter #13
Not sure about the DPF/cat MOT rules, i've never heard of a car failing these as diesels aren't tested on emissions

Good thing i have a friendly MOT test centre ;)
 

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Thanks for the clarification.... mines a 2007 so will be ok anyway, although the tester didnt seem too convinced even after he spoke to VOSA (and mine is the local training centre too!)
 

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Hello! I want to get rid of the catalysts on my Brera 3.2Q4. What troubles can I expect? Do I have to do chip tuning after removing catalysts? Will "Check Engine" appear after removing the catalyst? Thanks in advance for your answers!
 

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Hello! I want to get rid of the catalysts on my Brera 3.2Q4. What troubles can I expect? Do I have to do chip tuning after removing catalysts? Will "Check Engine" appear after removing the catalyst? Thanks in advance for your answers!
You will need a remap yes...
 

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Remap should be made specifically for a car without a catalyst or it can be simple Autodelta remap? Will i see "check engine" after remap or not?
 

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Discussion Starter #20
Hello! I want to get rid of the catalysts on my Brera 3.2Q4. What troubles can I expect? Do I have to do chip tuning after removing catalysts? Will "Check Engine" appear after removing the catalyst? Thanks in advance for your answers!
Not sure about where you are, but removing a cat on a petrol in the UK will result in MOT failure
 
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