Alfa Romeo Forum banner

1 - 12 of 12 Posts

·
Registered
Joined
·
7,047 Posts
Discussion Starter #1
I removed the cat on my 2.4 and it really improved the motor a lot.
Boost pickup is a lot faster and the boost actually went up slightly.
Fuel consumption improved marginally.
Regens take a lot less time to complete as well.
A proper decat pipe will work a lot better but it was a spur of the moment removal so we just gutted the cat.
On the upside the Agents will not know that it was removed.
 

·
Registered
Joined
·
7,047 Posts
Discussion Starter #3
From what I have heard they are not testing for it on Diesels so you should be fine.
If you get a decat pipe it is easy enough to replace the cat before you take it for MOT
 

·
Registered
Joined
·
197 Posts
From Jan 2012 the MOT changes and if a Cat was fitted at new it has to still be there to pass MOT. As there is no "Cat Test" for diesels I can't see how they can check the Cat is still inside if you have just gutted it but will shortly fail if there is a De-cat pipe fitted.

Reading the rule book it is for Cat's but not sure how many garages will get the technical difference between a Cat which actively converts gasses as they run though and a DPF which just filters!!! They might start failing cars which have had the DPF Removed even though it is in no way a catalytic converter!!!

Think I'll leave all my gubbins on though just to be sure and also as I do a lot of motorway miles reducing the problems associated with Regens for people that do a lot of town work. (You watch it all go to s***e now I've said that):rolleyes:
 

·
Registered
Joined
·
1,327 Posts
where is this cat actually installed? I looked everywhere, even left a can of cat food opened in the car, but no luck? :confused:












...sorry, couldn't just resist :D
 

·
Registered
Joined
·
1,327 Posts
on a serious note, you said regens take a lot less.. if you remove your cat I don't think you need regens anymore? Shouldn't it be remapped?
 

·
Registered
Joined
·
7,047 Posts
Discussion Starter #9
:lol: Regens are for the DPF. No you do not need a remap for the cat but like with all mods it will help. Did you try putting the cat food in the exhaust pipe
 

·
Registered
Joined
·
223 Posts
Won't this cause problems to your DPF?

I thought that the extra injected fuel that leaves the engine unburnt during regen, burns in the cat, and leaves the cat as hot exhaust gas that heats up the DPF.

Now the diesel is being burnt in the DPF, and not in the cat.
 

·
Registered
Joined
·
27 Posts
Won't this cause problems to your DPF?

I thought that the extra injected fuel that leaves the engine unburnt during regen, burns in the cat, and leaves the cat as hot exhaust gas that heats up the DPF.

Now the diesel is being burnt in the DPF, and not in the cat.
As I understand turbonutters removed the pre-cat behind the turbo. The 2.4 as well as the 1.9 in the 159 have a second main-cat direct before the DPF. So the fuel will burn there.
Your are absolutley right - you need the cat for heating up/burning the DPF.

Cheers Tom
 

·
Registered
Joined
·
7,047 Posts
Discussion Starter #12
Yes it is the precat just behind the turbo.
I was concerned about the DPF response with it removed.
Fortunately it reacted the way I thought it would and the regen response improved with all the heat being generated next to it and not behind the turbo in the precat
 
1 - 12 of 12 Posts
Top