Any k03/s owners have negative comments about 3" downpip/decat?

paultownsend · Dec 18, 2013

As above really, any negatives or downsides? Im going to fit one of the generic ebay 3" downpipes, then at a later date fit a Magnaflow 3" 200cel sport cat welded in. I have heard internet stories of old turbo's not liking the change in pressure and spitting their seals though the back box. It will be mated to a diesel straight through mid pipe ad OE rear box. RegardsPaul

16Klappe · Dec 18, 2013

What?

Just get it fitted, they are great.

I ran one for two years on a standard back box, as do 1000's of people.

**** the internet, if it's not ASN endorsed its probably bull****.

kwistof · Dec 18, 2013

16Klappe said:
**** the internet, if it's not ASN endorsed its probably bull****.

I like this, but I cannot 'like' it as the website is not playing ball

paultownsend · Dec 18, 2013

16Klappe said:
What?

Just get it fitted, they are great.

I ran one for two years on a standard back box, as do 1000's of people.

**** the internet, if it's not ASN endorsed its probably bull****.

Top chaps! My current flexi is leaking hence the need for a replacement. I'm hoping it will make the thing sound a little better too. Currently sounds like a wet fart

A3-Lee · Dec 19, 2013

I wouldn't even bother with the sports cat bud 3 inch downpipe and decat is a win

paultownsend · Dec 19, 2013

There has been a few Vosa vans in the area recently. I wouldn't want to risk it.

kimhemm · Dec 19, 2013

A3-Lee said:
I wouldn't even bother with the sports cat bud 3 inch downpipe and decat is a win

If you get a good cat in there, the difference is really very small in power

It's only if you want to use launch control it will make a big difference

16Klappe · Dec 19, 2013

kimhemm said:
If you get a good cat in there, the difference is really very small in power

It's only if you want to use launch control it will make a big difference

I don't know who you are, but I don't like your attitude.

kimhemm · Dec 19, 2013

16Klappe said:
I don't know who you are, but I don't like your attitude.

16Klappe · Dec 19, 2013

kimhemm said:

Sorry, I wasn't very clear there. I meant to say; you're wrong.

Flow is flow, and a restriction in flow reduces power.

Filling up your exhausts path with a catalytic converter is a great way of reducing flow. By all means bring up the legality of removing your cat, but why you would ever remove your cat, have it mapped out and then replace with a sport car I will never know.

Prawn · Dec 19, 2013

he's right though jardo, the power difference between a high quality free flowing sports cat and a decat is very small.

Don't be so obnoxious all the time!

kimhemm · Dec 19, 2013

16Klappe said:
Sorry, I wasn't very clear there. I meant to say; you're wrong.

Flow is flow, and a restriction in flow reduces power.

Filling up your exhausts path with a catalytic converter is a great way of reducing flow. By all means bring up the legality of removing your cat, but why you would ever remove your cat, have it mapped out and then replace with a sport car I will never know.

I have done the test on a remapped 1.8T and the difference was 2 HP without a cat compared to a good free flowing sports cat

So no, I don't really think I'm wrong and have a bad attitude

kimhemm · Dec 19, 2013

Prawn said:
he's right though jardo, the power difference between a high quality free flowing sports cat and a decat is very small.

Don't be so obnoxious all the time!

Exactly. Unless you are talking 4-500 HP and launch control a free flow 100/200 cell sports cat will be just about as good as no cat

16Klappe · Dec 20, 2013

I don't care.

Why would you run a CAT, regardless of how slight the restriction is if you didn't have to.

If sports cats are so great why don't you fit one Prawn...

kwistof · Dec 20, 2013

kimhemm said:
I have done the test on a remapped 1.8T and the difference was 2 HP without a cat compared to a good free flowing sports cat

So no, I don't really think I'm wrong and have a bad attitude

What make was the 'good free flowing sports cat' out of interest?

Prawn · Dec 20, 2013

16Klappe said:
I don't care.

Why would you run a CAT, regardless of how slight the restriction is if you didn't have to.

If sports cats are so great why don't you fit one Prawn...

Because I'm cheap and won't pay for one.

You're right in that ultimate power will indeed come from a decat over a sports cat, but for those not able / willing to swap it out every year, or find a friendly MOT place, if they can afford it without issue, a sports cat is only going to cost them a few bhp and save them a load of hassle.

paultownsend · Dec 21, 2013

I'm looking at the magnaflow cats. Circa £90.
There used in the 42 draft exhausts and also in magnaflow's own systems. 100 or 200 cel.

ShoozY · Dec 21, 2013

I ran one of the eBay downpipe and decat for a couple of years on a mk4 golf I used to have, the car was remapped before I fitted the downpipe, already had a non res cat back, the car was nippy and sounded goof, however when the downpipe was fitted it sounded evil on boost í ½í¸, I was hitting boost hard and really early in the rev range, go for it mate you will love it!

paultownsend · Dec 23, 2013

well offered £70 for the decat and its been delivered! just need to order gaskets and bolts from TPS and its a cold day in the garage!
Does anyone have any tips or hints for changing the DP?

jamiebennett81 · Dec 23, 2013

it doesn't work either way really

running decat is illegal but the best for "flow" option, you just need a friendly MOT station

running a 100cell or even 200 cell cat is almost pointless as again it won't pass emissions (certainly an old one won't) and so you are then stuck with a cat, which is restricting flow, and still won't pass an MOT....you might as well run with no cat (the only advantage being it looking semi legal should you get stopped by a clued up copper)

or if you are that scared of getting done, then run a cat, but then this negates the point of a 3" DP as you still have a bottleneck to your flow.

I think sports cats are a con, as you have to get them very hot to pass emissions (from my experience most of them don't) and when they don't pass (normally if you take it to a joe public MOT test station) you have wasted £££ on a "sports" cat which is illegal, and restricting flow

paultownsend · Dec 23, 2013

Just read your Leon thread. Superb work.
Only from reading around on the net, but I don't think I have heard of many people failing the MOT requirements from a 200cel cat. The magnaflow's get good reviews, but mostly in the Imprezza world.

Whst are the implications if busted by the law if running no cat? Fine? Points? Or soap on a rope for the showers?

kimhemm · Dec 23, 2013

I have had quite a few customer with the APR DP on the 2.0 TFSI going through MOT here in Denmark with no problems. That's with a 200 cell cat and they where doing fine and with good margin to the limit

jamiebennett81 · Dec 27, 2013

paultownsend said:
Just read your Leon thread. Superb work.
Only from reading around on the net, but I don't think I have heard of many people failing the MOT requirements from a 200cel cat. The magnaflow's get good reviews, but mostly in the Imprezza world.

Whst are the implications if busted by the law if running no cat? Fine? Points? Or soap on a rope for the showers?

Thanks

Depends on a few factors like the age of the cat. I had a 100 cell (or was it 200) and when new it would pass the MOT (although had to be made very hot)

What are the implications...well that depends on how nice the copper is who stops you. If there is a sports cat, then the copper I doubt would ever say anything or wouldn't ever notice.

they could give you the standard notice, for you to put a legal cat on, get it retested etc, but I can't see how they would even get to that point really, you would have to be very unlucky.

paultownsend · Jan 9, 2014

Well. Fitting that was fun!
A good soak in duck oil meant no snapped studs. Extensions and wobble bars are a must.
Getting it all bolted up was a nightmare. Had to chop down a 17mm spanner to get access.

Well, on warm up idle it loud (using tdi straight middle and OE rear box). But once warmed up it's quite subtle. I don't think il ever upgrade the exhaust now.

It pulls now from 2k. Harder, and revs higher. It's great. Feels noticeably quicker. Gotten by was perfect. Fits right up to theOE exhaust.

And what I'm most please about, no cracks in my K03 exhaust side!

Shame the rear beam brake rubber pipe burst on the way home

Any k03/s owners have negative comments about 3" downpip/decat?

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