D40 De-cat

BAWSACK · Jan 3, 2010

Thinking of drilling out my D40 Euro 4 cat internals tomorrow.....has anybody done this yet?

I know there has been a lot of talk about this on the site regarding exhausts and de-cat pipes etc but the obvious one to me is just remove the cat and drill out the internals to aid performance??

I have had previous experience with this method on Scania trucks where ones fitted with Eminox pollution reducing stacks have an internal baffle catalyst to aid emissions and thus being able to qualify for cheaper road tax....Although the cheaper road tax is great these stacks do restrict the trucks somewhat! so to overcome this the internals are removed and when the truck goes for plating a temporary exhaust stack is fitted for the test :roll: The power difference is really apparent when you change the pipes and I would suggest this must be the same on the Navara...........

:cheers2:

The-Elite · Jan 4, 2010

Do it and let us know how difficult it is.

Might try getting it done on mine.

BAWSACK · Jan 4, 2010

Done the de-cat this morning, took about 3 hours and was a little tricky to remove the downpipe. Once I had the exhaust off it only took minutes to knock out the internals of the catalyst....

Test drove the truck and it's definitely better with performance, the turbo is a lot more apparent and the exhaust note has changed very slightly. Truck is night and day and it pulls a lot better in 2nd + 3rd gear.

Would really advise you all to do it as it was well worth braving the cold for a couple of hours - you will not be dissapointed! the best bit it as well was, it didn't cost me a penny!!!

Some pics of before and after...

BAWSACK · Jan 4, 2010

The last pic of the internals removed

Lil'Trucker! · Jan 4, 2010

Nice job mate :thumbright: just wondering though, what happens when it's MOT time? :scratch:

dejongj · Jan 4, 2010

Well done! Likewise I wonder what happens MOT time during the emissions test? That and getting the Copenhagen lot following you :lol:

BAWSACK · Jan 4, 2010

Shouldn't be a problem come MOT time, I'm confident it will still pass the emission test but if not my mate owns a garage so getting it through will be no sweat.

Andy · Jan 4, 2010

Great job!

But was there any sensors AFTER the cat?? JUst thinking if there is, might be the possiblity of a engine managemant light coming on?! this happened to me with a saxo once when i decatted it.......

BAWSACK · Jan 4, 2010

Andy,

No sensors after the cat... have test driven today about 50 miles and as yet no warning lights etc

will keep you all posted if there are any problems.

Cheers lads :cheers2:

Andy · Jan 4, 2010

Great!!! could be a weekend project if this snow stops!!! :thumbright:

The-Elite · Jan 4, 2010

Hopefully it won't cost me a penny either.

Well okay, I'll get my cousin a kebab after he's done it. 8) :lol:

artycheer:

Lil'Trucker! · Jan 4, 2010

The-Elite said:
Hopefully it won't cost me a penny either.

Well okay, I'll get my cousin a kebab after he's done it. 8) :lol: artycheer:

Chillie sauce? :wink:

The-Elite · Jan 4, 2010

And garlic. :wink: :salute:

EDIT: Damn, it's making my mouth water thinking about it.

shorny · Jan 14, 2010

BAWSACK said:
Shouldn't be a problem come MOT time, I'm confident it will still pass the emission test but if not my mate owns a garage so getting it through will be no sweat.

According to my local exhuast fabricator, there are no requirements for diesels to have a cat installed (they only do it for emissions!)
so come MOT time it should have no issues. :wink:

BAWSACK · Jan 14, 2010

Sorted M8..........the only downside I've noticed so far with the cat removed is on tickover the diesel fumes (smell) exiting the exhaust are more present. But the power etc gained by removing it is worth it in my opinion.

Andy · Jan 14, 2010

BAWSACK said:
Sorted M8..........the only downside I've noticed so far with the cat removed is on tickover the diesel fumes (smell) exiting the exhaust are more present. But the power etc gained by removing it is worth it in my opinion.

well thats nothing to worry about then!! :lol:

tuju77 · Jan 15, 2010

BAWSACK said:
Sorted M8..........the only downside I've noticed so far with the cat removed is on tickover the diesel fumes (smell) exiting the exhaust are more present. But the power etc gained by removing it is worth it in my opinion.

So, did u replace the cat with another pipe?sorry for the dump question :mrgreen:

U reckon this is better than putting a 3" exhaust all the way from turbo back to end muffler?

BAWSACK · Jan 15, 2010

I just removed the cat internals from the standard exhaust. Not sure about what you suggest with the use of a 3" pipe, someone else who's done this mod would be best to comment about it.

tuju77 · Mar 10, 2010

How do you remove the cat inside?I tried and no luck except by destroying the honed inside and I don't want to do it.

HELPPPP pliss

ale:

BAWSACK · Mar 18, 2010

Sorry for the late reply, not been on for a while. I just chapped out the internals, there are two baffle type arrangements inside that chap out quite easy. :thumbright:

jackhon · Aug 19, 2010

I DO DECAT TOO......GREAT........POWER BAND BATTER LOT.......

D40 De-cat

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