2.0 TDI exhaust

[dimsim]

Im thinking of modding the exhaust on my mk v. Has anyone done this ? I went to different exhaust shops and 1 said chuck the lot and replace it all with bigger pipes and muffler, the other said to leave it as is , it was all ok because the rear muffler has no baffles in it. Any advice welcome. Thanks.

[Greg Roles]

I'm "about" to do the same thing, but I've been saying that for several weeks now ( lack of play time! ). The stock pipe is mandrel bent at 2.5" and it would flow pretty well. Then again you can never oversize a turbo exhaust. Thing is the MAJOR restriction is right next to the turbo, the DPF particulate filter. Upping the pipe size and leaving that in place is a waste of time and money really.

Nearly all the aftermarket "cat" (DPF ) back exhausts available delete the huge rear pancake muff. I am going to do that for sheer weight savings alone! I'd consider replacing the rear axle area resonator if it turns out to be restrictive, with a nice flowing Jap one, but I'd hazzard a guess that's not going to be necessary.

My vote would be cutout the big rear one, as it'll be cheap and quite easy for a shop to do, and see if the car feels any better. Go from there!

[Mischa]

greg his car doesnt have a DPF that lucky bugger :duh:

[dimsim]

On my wish list is a larger free flow cat, I would keep the resonator and do something with the rear muf(if it is as restrictive as some people say) . I need the car to be quiet as my wife drives the car now with bubs in the back and she who must be obeyed will not stand for a loud exhaust.

[gldgti]

i wouldnt be scared about making it loud - the turbocharger is the worlds most expensive muffler.

my 1.9TD has mandrel 2.5" all the way from the turbo with resonator and a small straight through perf rear box, and its DEAD quiet. quieter than stock i reckon. turbo outlet is so small it just kills all the noise.

[Greg Roles]

I've been told the diesel with no muffs etc is quite reasonable.
Personally to avoid the drone, keep a resonator at least!

[Transporter]

It is not cheap.

http://www.dieselpowermag.com/tech/general/0810dp_diesel_exhaust_dpf_delete/index.html

[gldgti]

emissions laws are all so backward....

all this faff trying to pull harmless soot out of the exhaust, and in the process make the entire thing less efficient, hence burn more fuel for your mile.

what they should be doing is taxing heavily any vehicles with a large displacement/weight ratio - so 6.2L V8 commodores get BIG emissions tax, and little 1.4TSI's and vw diesels get no emissions punishment.

why should I have to put up with an inefficiency such as a CAT or DPF, if i already choose to drive an economical car?

[gregozedobe]

what they should be doing is taxing heavily any vehicles with a large displacement/weight ratio - so 6.2L V8 commodores get BIG emissions tax, and little 1.4TSI's and vw diesels get no emissions punishment.

A fairer way of doing it would be to increase the tax on fuels (and also reduce rego, 3rd party, import duty, sales tax etc at the same time). Think about the concept for a moment before you all go running around screaming like headless chooks.

The more you drive, the more fuel you use, the more tax you pay. If you drive something thirsty (V8 commodore), but only travel 5,000Km a year why should you pay as much tax as someone who drives the same vehicle 35,000Km a year.

Similarly someone who drives a 1.9 Polo 100,000Km a year is also using a lot of fuel (and creating a lot of pollution), even though their vehicle is very economical. Why should they only pay the same tax as granny who only drives 12,000Km a year ?

If the recent high fuel prices had continued, we would have seen a big shift towards saving fuel. Shorter, less frequent trips, less "pleasure" driving in the short term, and moves towards more fuel efficient vehicles in the long term.

Of course politicians being what they are, we'll probably get higher fuel taxes WITHOUT the reduction in rego and all the other govt charges :frown:

[Transporter]

A fairer way of doing it would be to increase the tax on fuels (and also reduce rego, 3rd party, import duty, sales tax etc at the same time). Think about the concept for a moment before you all go running around screaming like headless chooks.

The more you drive, the more fuel you use, the more tax you pay. If you drive something thirsty (V8 commodore), but only travel 5,000Km a year why should you pay as much tax as someone who drives the same vehicle 35,000Km a year.

Similarly someone who drives a 1.9 Polo 100,000Km a year is also using a lot of fuel (and creating a lot of pollution), even though their vehicle is very economical. Why should they only pay the same tax as granny who only drives 12,000Km a year ?

If the recent high fuel prices had continued, we would have seen a big shift towards saving fuel. Shorter, less frequent trips, less "pleasure" driving in the short term, and moves towards more fuel efficient vehicles in the long term.

Of course politicians being what they are, we'll probably get higher fuel taxes WITHOUT the reduction in rego and all the other govt charges :frown:

Very good point there, also there would be less idiots on the road wasting fuel.:)

[Gigitt]

I'm "about" to do the same thing, but I've been saying that for several weeks now ( lack of play time! ). The stock pipe is mandrel bent at 2.5" and it would flow pretty well. Then again you can never oversize a turbo exhaust. Thing is the MAJOR restriction is right next to the turbo, the DPF particulate filter. Upping the pipe size and leaving that in place is a waste of time and money really.

Nearly all the aftermarket "cat" (DPF ) back exhausts available delete the huge rear pancake muff. I am going to do that for sheer weight savings alone! I'd consider replacing the rear axle area resonator if it turns out to be restrictive, with a nice flowing Jap one, but I'd hazzard a guess that's not going to be necessary.

My vote would be cutout the big rear one, as it'll be cheap and quite easy for a shop to do, and see if the car feels any better. Go from there!
Do it!

It's called a Mufflerectomy.

I did it to my Mk3 TDI back in Oct 2006 the night before Drag Warz.

Sound is Tough and not loud by Milo tin standards.

My TDI now rev's quicker and easier.

2.5in Stainless Mufflerectomy:
http://i226.photobucket.com/albums/dd246/gigitt/Mufflerectomy/IMG_0450.jpg
http://i226.photobucket.com/albums/dd246/gigitt/Mufflerectomy/IMG_0453.jpg
http://i226.photobucket.com/albums/dd246/gigitt/Mufflerectomy/IMG_0465.jpg
http://i226.photobucket.com/albums/dd246/gigitt/Mufflerectomy/IMG_0473.jpg
http://i226.photobucket.com/albums/dd246/gigitt/Mufflerectomy/IMG_0475.jpg
http://i226.photobucket.com/albums/dd246/gigitt/Mufflerectomy/IMG_0476.jpg

[GoLfMan]

The more you drive, the more fuel you use, the more tax you pay. If you drive something thirsty (V8 commodore), but only travel 5,000Km a year why should you pay as much tax as someone who drives the same vehicle 35,000Km a year.

Similarly someone who drives a 1.9 Polo 100,000Km a year is also using a lot of fuel (and creating a lot of pollution), even though their vehicle is very economical. Why should they only pay the same tax as granny who only drives 12,000Km a year ?

If the recent high fuel prices had continued, we would have seen a big shift towards saving fuel. Shorter, less frequent trips, less "pleasure" driving in the short term, and moves towards more fuel efficient vehicles in the long term.

Of course politicians being what they are, we'll probably get higher fuel taxes WITHOUT the reduction in rego and all the other govt charges :frown:

New Zealand has a system like this in place for diesel cars, you "buy miles" when you regester the car and you pay that fee every year. They only do that however because Diesel fuel over there isnt heavily taxed like ours and is cheap as a consequence.

i guess us Aussie diesel drivers just get the bill for the road milleage usage every time we hit up the pumps!

[CatonaPC©]

Aside from any issues about whether removing a muffler/resonator affects the ECU and in turn, driveability, the question one must ask, is any of this legal?

Probably not.

That nice big chrome exhaust outlet looks impressive but it's a sure fire way of attracting the attention of the p-o-l-i-c-e and jealous Civic drivers.

[Vicbitter]

Hey Gigitt, hows it feel now with the new exhaust.

[Gigitt]

I did it just over 2 years ago. Not pa problems with it.

Feels great. Enghine responds better. Car Pulls Harder and engine revs free'er.

Only problem now is I have to get a bigger turbo!

[Vicbitter]

greg his car doesnt have a DPF that lucky bugger :duh:

i have the 103kw with apparently with no dpf (i read in the dpf thread)

so....i could put an aftermarket muffler on it relatively easy with no major probs?

[Greg Roles]

Absolutely VB, you could do a full turbo back exhaust if you really wanted to.

[Vicbitter]

I haven't measured it yet but i think i got the 2.25" piping.
I really wanna get rid of the stock muffler and attach something better!
Would i really get much of a gain in anything? other than looks.

[Greg Roles]

Possibly a bit better response, but I would expect little from a simple muffler delete. I am of the opinion that the CRD does come with DPF, as ALL new VW diesels to most counties do from now on to meet the new forthcoming emission rules. If anything that's by far the biggest exhaust restriction, and not an easy thing to delete. Better to await a chip for your car if you want some more berries.

Looks like you have the typical VW huge pancake rear muff. I'd guess you have a resonator before the rear axle, in which case I'd be tempted to do a delete anyhow...what I'm planning for sure.

Shame you got ripped off at 2.25, my VW is 2.5 mandrel all the way baby!

[Vicbitter]

Funny thing is, i was reading the manual and no where does it state it's got a dpf!! Mentions cat converters but no particle filters......

I even called jeep, and on their systems there is no mention of dpf.
So it leads me to believe if it has no dpf, (gotta be a tdi then?) less restriction on a exhaust mod.
I guess i would have to wait till the warranty runs out to do it:duh: 3 yrs from now......

[Transporter]

Funny thing is, i was reading the manual and no where does it state it's got a dpf!! Mentions cat converters but no particle filters......

I even called jeep, and on their systems there is no mention of dpf.
So it leads me to believe if it has no dpf, (gotta be a tdi then?) less restriction on a exhaust mod.
I guess i would have to wait till the warranty runs out to do it:duh: 3 yrs from now......


PD or CRD VW calls their diesel engines TDI regardless.
Both can have DPF.

[stark27]

I had an exhaust place experiement on my car for 2 weeks to try and get a note out of it. Went through 10 resonators and did everything imaginable. Still no noticeable difference. But it took a fair chunk of weight out.

[comfortline]

Any more grunt?

[stark27]

Any more grunt?

No, nothing I could notice.

[Greg Roles]

very interesting, seems that the stock exhaust, at least post DPF is flowing very well. It certainly "looks" good, 2.5" and mandrel bends, so it appears the stock muff and resonator are flowing well if swaping gave no noticable effect.

Damn!:duh:

[comfortline]

Cogdoc,

Probably the DPF is the major restriction.

DPF delete anyone?

[Greg Roles]

Absolutely is, but you have to give it to VW that they can still make the GT perform so well stock WITH an ultra restrictive DPF.

It can be removed, but personally I'm not too keen to start smoking everyone out, I hate folowing smokey diesels.

[comfortline]

I think its a hoot. You deploy the smokescreen, and then you vanish.

[Vicbitter]

Punch it, smoke it, leave 'em behind

[gregozedobe]

Trouble is, every time you do that you are adding another person to the majority who currently think - "Ugh ! Diesels are horrible polluting things, next time a politician wants to totally ban them I'll give them my vote." And you know where that will end up - no diesels allowed on the road at all :(

[Greg Roles]

And I'm one of them!

Then again what a non DPF TDI puts out compared to an old 4x4 is nothing....it's those old guys who obviously have dirty injectors that pump out gallons that really bug me....especially if I'm on the pushie...YUCK!

[gregozedobe]

But unfortunately ALL diesels get "tarred with the same brush", and it is such a noticeable pollution in some cases. Although I have seen a few crappy petrol cars that are so worn out thet they produce nearly as much smoke.

I just wish there were more cops on the road (and roadworthy inspectors). There are so many obviously unroadworthy vehicles out there that they would actually make money from the exercise, as well as making the roads safer for the rest of us (Jeez, showing my age there ! ).

[Greg Roles]

You'll find the gov will have a "smokey vehicle hotline" where you can dob people in and they get a letter, and on their third strike they have to report for an inspection. I have no problem narking in the very bad ones you see every few weeks, it's only a letter, but hey it's something.

Guess I'll have to keep my DPF lest I get narked!

[Greg Roles]

But unfortunately ALL diesels get "tarred with the same brush", and it is such a noticeable pollution in some cases. Although I have seen a few crappy petrol cars that are so worn out thet they produce nearly as much smoke.

I just wish there were more cops on the road (and roadworthy inspectors). There are so many obviously unroadworthy vehicles out there that they would actually make money from the exercise, as well as making the roads safer for the rest of us (Jeez, showing my age there ! ).

Speed camera has a much higher profit margin, doesn't take sickies, and works for pittance!

Now back to TDI exhausts! ( you're gonna get me in trouble mate! )

[gregozedobe]

Now back to TDI exhausts! ( you're gonna get me in trouble mate! )

Naah, we've been ON Topic the whole time ;)

TDI exhausts with DPF = no soot= no problems with the wider motoring public (but potentially less power if you want to remap)

TDI exhaust without DPF = soot = possible problems with the wider motoring public (but potentially more power if you want to remap)

[comfortline]

That's a great synopsis. But does the level of smoke equate to that of any Mitsubishi with 100,000 km on the clock?

No I don't think so!

[gregozedobe]

A lot depends on the state of wear and tune of the individual vehicle (and some are particularly poorly maintained).

Soot is simply unburnt diesel fuel. This is mostly caused by worn/clogged injectors not atomising the fuel droplets properly, but some "tuners" simply adjust up the fuel supply adjustment on the injector pump, and if there is insufficient air to burn all the fuel then you will also get more soot. If taken to extremes this can also raise combustion temps to the point of mechanical failure.

I agree that most of the truly awful producers of great big black clouds of soot need some serious attention to their injectors, rather than being a modern TDI sans DPF.

[Vicbitter]

Whiteish/grey smoke ok?

[gregozedobe]

Not usually.

Unless it is only condensation from a cold motor and cold exhaust when it is OK (it should go away when everything warms up to normal operating temperatures).

If it is burning lots of oil then not so good (could be rings, valve seals or turbo problems) :(

If it is a petrol then it may be over-fuelling by a fairly large margin (but this is the diesel section, so I'm assuming you aren't talking about a petrol engine).

[Vicbitter]

only when i give it a bit, and then only sometimes... (done 4,500km)

[gregozedobe]

only when i give it a bit, and then only sometimes... (done 4,500km)

Any particular pattern to the "sometimes" ? Eg if it only ever happens when you take off hard after idling for a while (eg at lights) then it might be valve seals.

Is your engine's performance (power) consistent and OK, or does it vary or is it a bit slower than other cars with the same engine and gearbox ?

Does it use any oil, and does it use more around town or in highway running ?

[Vicbitter]

I noticed after a few days of revving past 3,000 in gear shifts, seems to be less smoke now. Maybe just needed a cleanout!