De-cat causes problems on vrs?

[EuanTdi]

Hey people,

was looking up what exhaust to get and was looking at de-cat milltek turbo back but i also saw that it can cause the turbo to go..oil seals think it was?

is this true or will it be okay? anyone got the best set up to go for or company is best?

thanks euan

[Guest BigJase88]

turbo as it is, is rubbish....

so any mod is at your own risk...

personally i'd uprated to a pd150 or pd150 hybrid turbo before i messed with anything

[TrevorB33]

been covered a billion times before, search is your friend

general thoughts seem to be

Decat on Remapped car mapped for decat = Okay

Decat on Standard car = Okay

Decat on Remapped car not mapped for decat = bad

[TissMe]

Decat on a diesel will cause no issues at all

This is because there are no lambda probes on diesels

So do it if you want

May be worth doint the full sysyem at the same time though

This is due to the decat being of a larger bore on the exhaust

Sarah

[Guest BigJase88]

Decat on a diesel will cause no issues at all

This is because there are no lambda probes on diesels

So do it if you want

May be worth doint the full sysyem at the same time though

This is due to the decat being of a larger bore on the exhaust

Sarah

depends on type...

magnex decat and system is a direct replacement for the oem system... 2.25"

Milltek on the other hand is completely different and 2.5"

[TissMe]

depends on type...

magnex decat and system is a direct replacement for the oem system... 2.25"

Milltek on the other hand is completely different and 2.5"

Never had anything to do with Magnex , thank god

But hey , tes you are correct Milltek is a larger bore

I wonder if that will improve the BHP and torque of the car as it is a larger bore

Oh yes it will

Sarah

[wja96]

As I understand it there is no performance benefit to decatting a diesel, or from making the exhaust bigger unless the car is remapped, and even then the benefits are negligible. From recollection the problem is that the reduced back-pressure from the decat causes the turbo to spool up too fast and that kills it fairly quickly. A hybrid turbo does not have this problem, so there is no danger there.

[TissMe]

As I understand it there is no performance benefit to decatting a diesel, or from making the exhaust bigger unless the car is remapped, and even then the benefits are negligible. From recollection the problem is that the reduced back-pressure from the decat causes the turbo to spool up too fast and that kills it fairly quickly. A hybrid turbo does not have this problem, so there is no danger there.

No

If you make the exhsut larger , yes you are getting rid of the gasses quicker , so will get a benifit from a larger exhaust

If it is remapped , then you will see more of a benifit

Back pressure is not an issue on the vRS

Sarah

[wja96]

No

If you make the exhsut larger , yes you are getting rid of the gasses quicker , so will get a benifit from a larger exhaust

If it is remapped , then you will see more of a benifit

Back pressure is not an issue on the vRS

Sarah

So what extra power would you expect from a decat?

And then from increasing the exhaust from the standard 2" to 2.5"?

With rolling road printouts if you don't mind as what you are saying is totally contrary to everything I have been told by tuners (including Awesome) over the last 4 years.

[EuanTdi]

so i'll be fine to a milltek de-catd system on it then yeh?

[XLBaconDoubleCheese]

so i'll be fine to a milltek de-catd system on it then yeh?

If it's not already mapped then yeah should be. But you get little or no gain, and could quite possibly have to refit it in the future with the changes to MOT's etc. I'd just spend the money elsewhere tbh

Matt

[EuanTdi]

If it's not already mapped then yeah should be. But you get little or no gain, and could quite possibly have to refit it in the future with the changes to MOT's etc. I'd just spend the money elsewhere tbh

Matt

sorry mate yes it has been mapped and has pd160 intake

Euan

[martyn1976]

sorry mate yes it has been mapped and has pd160 intake

Euan

Mine had the milltek de cat full system an the revo map all done the same day and has been driven every day since and no probes at all  ( about 1000 miles ) I also have he pd160 intake and green filter hope this is some help 

[XLBaconDoubleCheese]

Yes because yours was mapped to run a decat. If you stick a Decat on a car mapped to run the cat, that's what causes the overspooling.

Matt

Edited 4 January, 2011 by matt1chelski

[EuanTdi]

awww great so im going to have to get it mapped again just for an exhaust?

Euan

[expostmanpat]

I ran a std vRS on a decat (full Miltek) for 30K + miles

The car was driven probably harder at greater speeds and more extreme conditions than most fabias.

At no point did I ever have any problems, engine lights narder.

I never bothered putting the car on a rolling road either before or after, I would say it made a difference, but no proof whatsoever.

You pays your money and takes your chance.

[XLBaconDoubleCheese]

awww great so im going to have to get it mapped again just for an exhaust?

Euan

Exhaust would be ok, but I'd rather not risk a decat without getting the map tweaked.

Matt