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TDI de-cat?


biggaz
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Eyup Gaz

Do it mate! Nothing off the shelf but its easy enough for any custom exhaust place to do.

My recommendation would be to get a FLANGE to fit the turbo and have a 2" downpipe made up for it !

This way your turbo will spool up a little bit quicker and you'll get your peak torque faster!

I've got a Milltek Largebore downpipe on my Bora with No-Cat and it made a fair bit of difference ! TBH It improved the economy a little more as well :)

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Eyup Gaz

Do it mate! Nothing off the shelf but its easy enough for any custom exhaust place to do.

My recommendation would be to get a FLANGE to fit the turbo and have a 2" downpipe made up for it !

This way your turbo will spool up a little bit quicker and you'll get your peak torque faster!

I've got a Milltek Largebore downpipe on my Bora with No-Cat and it made a fair bit of difference ! TBH It improved the economy a little more as well :)

Ello mate

Im thinking of just asking powerflow to do me a de-cat, just a standard changeover piece so i can swap it back when i need to :)

Got one made from them for me mams motorhome (cat pinched!) and they charged £70 which was fair enough.

Mines just seemed a bit flat recently, wanna bit more but im tight :)

cheers gaz.

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Ello mate

Im thinking of just asking powerflow to do me a de-cat, just a standard changeover piece so i can swap it back when i need to :)

Got one made from them for me mams motorhome (cat pinched!) and they charged £70 which was fair enough.

Mines just seemed a bit flat recently, wanna bit more but im tight :)

cheers gaz.

To be fair, Your never going to need to change it back anyway as the laws don't currently require a cat on Diesels :)

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how much more power can be gained from this?

In conjunction with a remap it will help give better power gains, but if you are doing it on its own, or have already had a remap, It isn't going to gain you any peak power.

The best way I can put it is with this graph...

OK so Its not the best graph as a lupo TDI is never going to see this level of power. but here goes:

newgraph.jpg

The Blue line is a Completely Standard ASZ (130bhp) TDI engine with an Upgrade panel filter.

The Black line is the same ASZ engine with the Pannel filter and a Generic Remap.

The Red line is an ASZ engine with a Large bore downpipe and high flow exhaust system and a custom map.

If you look at the Torque line between 1,000 and 2,000 RPM, You will see that the red line rises much faster than the Black or Blue line does.

This is simply because now that the Catalyst has been removed, The turbo is much more free to breathe and as their are less restrictions it is allowed to spool up that little bit faster meaning that it hits peak torque sooner.

The other benefit of a de-cat on the TDI's is that you can hold the torque for longer allowing the car to be mapped past its original redline.

As you can see on the graph above, the custom remap takes power all the way to 5,000rpm!

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i was told that my map would adjust after the decat, is this wrong or should i get it redone?

It will adjust a tiny amount but only to the extra boost at low levels.

A map can't really take into consideration less resistance from the exhaust side of things without being amended.

Was your map a custom map (3 - 5 hour job) or was it a Generic map (30 mins - 1 hour job) ?

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It will adjust a tiny amount but only to the extra boost at low levels.

A map can't really take into consideration less resistance from the exhaust side of things without being amended.

Was your map a custom map (3 - 5 hour job) or was it a Generic map (30 mins - 1 hour job) ?

the map was taken off my ECU and sent to Darren @ G-Werks.. then sent back about an hour later and put back on... bit of both, all my figures were changed, and it cannot be used on another car. not a live map tho

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the map was taken off my ECU and sent to Darren @ G-Werks.. then sent back about an hour later and put back on... bit of both, all my figures were changed, and it cannot be used on another car. not a live map tho

So it is a generic map then...

Unless the car was either mapped on the rolling road or live on the road, it is not a custom map.

The ECU on your car is self learning so it will learn to a de-cat in some ways, but it won't have anywhere near the level of benefit that having a full custom map done once the de-cat is done.

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