I would have thought that you would be opening a whole can of worms by altering the exhaust set-up.http://www.motorhomefacts.com/modules/Forums/images/smiles/surprised.gif
To begin with, the quality of the co2 leaving your vehicle is now a measure against the taxation and this would be dramatically altered by removing the catalytic process.
The overall performance of your vehicle will be unbalanced if you alter the resistance of escaping gasses.http://www.motorhomefacts.com/modules/Forums/images/smiles/eek.gif
I am certainly not an authority but my head tells me that your ideas should not be followed through.
A

 

I would have thought the Cat has a Lamba sensor type device on it too which all vehicles with a Cat do

 

A lot of car modifiers take the cat out of performance cars to get more power out of them, it just means that you put out more noxious gasses, that are not converted by the CAT. I have known cars still get through the MOT without a cat but that would depend on the setup and the permitted emmissions for that vehicle.

 

I would have thought the Cat has a Lamba sensor type device on it too which all vehicles with a Cat do

Vehicles vary most have them on the manifold others have one before the Cat and some have them on part of the cat. There are ways round most things :wink:

 

I believe that in a couple of years there will be something in the mot test ref cats. If the vehicle was manufactured with one and it has been removed it will be a fail.

 

I would have thought the Cat has a Lamba sensor type device on it too which all vehicles with a Cat do

Only petrols, not diesels which (I think) only have a 2-way cat not a 3-way one.

Lots of diesel tuners de-cat them and it makes not a jot of difference at MOT time. Nothing a diesel cat does is tested by the emissions test, unlike a petrol test where it does matter.

Cats are the biggest con-trick ever foisted on the motoring public - I've heard it takes 10 years/120,000miles for them to save more pollution that it takes to make one.

 

Hi stanner,

Are you sure on that "stament" ? if so mines coming off and being sold on fleaby and straight pipe fitted.

i wonder if any sensors fitted to the Renault cat? that would upset the Ecu.

 

That is what I have been told, that it makes no difference on a diesel but it is required for petrol.

Of course if they just made them not so easy to steal or valuable there would be no issue.

 

The next stage is the Euro 6 engine which is already used in some trucks.

"Catalytic converters in diesel engines do not work as well in reducing NOx. One reason is that diesel engines run cooler than standard engines, and the converters work better as they heat up. Some of the leading environmental auto experts have come up with a new system that helps to combat this. They inject a urea solution in the exhaust pipe, before it gets to the converter, to evaporate and mix with the exhaust and create a chemical reaction that will reduce NOx. Urea, also known as carbamide, is an organic compound made of carbon, nitrogen, oxygen and hydrogen. It's found in the urine of mammals and amphibians. Urea reacts with NOx to produce nitrogen and water vapor, disposing more than 90 percent of the nitrogen oxides in exhaust gases".

http://en.wikipedia.org/wiki/European_emission_standards#References

 

Following rayc's advice, I may suggest a certain adaptation prior to driving..... and drink a lot. With a suitable adapter you may not even need to stop!http://www.motorhomefacts.com/modules/Forums/images/smiles/biggrin.gif
A

 

Hi stanner,

Are you sure on that "stament" ? if so mines coming off and being sold on fleaby and straight pipe fitted.

i wonder if any sensors fitted to the Renault cat? that would upset the Ecu.

All I can say is lots of diesel tuners do it and I haven't heard of any failing MOTs as I think the emission test for a diesel is just for smoke, as diesels don't produce much CO anyway.
The petrol test is for CO, as the cat converts the CO to CO2 and the Lambda sensor is what controls that reaction.
SFAIK diesel cats don't have any sensors - at least I haven't seen any (yet) however things are getting more complicated year on year.

 

Hi stanner,

Are you sure on that "stament" ? if so mines coming off and being sold on fleaby and straight pipe fitted.

i wonder if any sensors fitted to the Renault cat? that would upset the Ecu.

If I was you, I would just take it off and KEEP it in store just in case, it will cost a lot more to replace it new should you in future have to put one back on.

All our vans have had them removed until we get our new security fencing instaledl around the forecourt and loads of razor wire in the stotage yard, fed up with having them stolen.

At this rate we will be changing our name to 'Fort Knox Motorhome and Camping Centre !

Peter

 

Sorry Peter, could you just repeat that again?

SD :wink:

Mod Note : in case you are wondering what SD means ..Peter's post was done in triplicate... 2 of them now removed :lol:

 

Heard you the first two times Peter! :lol: :lol:

Didn't realise you had a stammer. 8O :lol:

Will fix it for you.

Dave

Faster Mod Note : I beat you to it :lol: ( spykal)

 

Peter are you just running them with straight through pipe or are these the ones on show?

 

That is what I have been told, that it makes no difference on a diesel but it is required for petrol.

Of course if they just made them not so easy to steal or valuable there would be no issue.

Just had my cat replaced after thieving scrotes helped themselves. Cost me 2yrs no claims and £250 excess on insurance.
Did some asking about (inc main dealer who replaced mine....wink,wink.... reply) about doing without a cat.
General concensus seems to be that cat removal is NOT a major issue!!!! Downside more fuel used, upside, better performance. Under present ruling, vehicle will / should still pass MOT.
Living on pins now in case the thieving bas***ds return for this one just before my intended hols.
Took 7wks for this replacement cat to arrive from Fiat Italy!!! :evil: :evil:

Ken (Voluntary hand remover on request) :twisted: :twisted: :twisted: :twisted:

 

Downside more fuel used,

Why should that be?

 

Downside more fuel used,

Why should that be?

Sorry Stanner, no idea! Just repeating the verbal info I have been given. Hope the info in total was correct, I put my trust in the "experts?" in this field.

Cheers,

Ken

 

Peter are you just running them with straight through pipe or are these the ones on show?

All vans on our premises not locked up in workshop have had their cats removed until our premises are fully protected.

(Bit noisy when we move them about but c'est la vie !)

Test drives we put one back on and take it off afterwards.

Peter

 

Thanks Peter, are you not convinced that shear nuts or cat clamps may work? you could incorporate it as a selling aid!.
Maybe you are too big a target and they would not stop your potential 'visitors'!

 

Downside more fuel used,

Why should that be?

Sorry Stanner, no idea! Just repeating the verbal info I have been given. Hope the info in total was correct, I put my trust in the "experts?" in this field.

Cheers,

Ken

I can't see why it should - but then that's "experts" for you.

As a cat is an obstruction to exhaust flow I can see why you would get more power/better response if it is removed (why the tuners do it) and I would expect that to result in better fuel economy as well.