straight pipe

den9

Veteran Member
Joined
Apr 9, 2007
Location
doylestown pa
TDI
04 Jetta
i want to do an exhaust on my jetta but im not sure what to get. whats the stock pipe diameter and should i do a full pipe from the cat back or just take the muffler off and add a tip?
 

Whitbread

Vendor , w/Business number
Joined
Jan 21, 2007
Location
Johannesburg, MI
TDI
Several
Just run straight pipe from the turbo back, it sounds awesome and isn't very loud at all. I cut open the cat and hollowed it out due to the offset inlets/outlets. The pipe is run all the way to the back with a turndown right at the edge of the bumper cover and you can't even hear exhaust noise on the highway. The grin from hearing the whistling and whooshing will never leave your face:).
 

Whitbread

Vendor , w/Business number
Joined
Jan 21, 2007
Location
Johannesburg, MI
TDI
Several
I meant a straight pipe as in no cat and no muffler, keeping the flex pipe, sorry for the confusion!
 
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Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
In my signature there is a link to what I did with my exhaust. In that page there is a link to a car with a cat & muffler ectomy for comparison. You can hear what it would sound like. There are also a few more videos on youtube of various tdi's

Cutting out the cat/muffler is the biggest bang for the buck as far as exhaust modifications. It's not much/any louder in normal driving, has a nice turbo whistle, and a nice sound when you get on the throttle. I believe there are gains to be had with a 3 or 4 inch exhaust over stock size, but it is 10x the cost of cat/mufflerectomy. If LurkerMike gets his pipes into production it looks like it will be a more cost effective option for the TDI community.

Just depends on what you want, how much you want to spend and how much work you're willing to put into it.
 

devonutopia

Top Post Dawg
Joined
Dec 1, 2003
Location
Devon, U.K
TDI
PD300 Skoda Fabia
I run 2.25" straight through from my downpipe, and getting big power has not been an issue. It seems as long as there's no fittings for the exhaust gases to have to go through, the size is fairly irrelevant. I know the gas comes so fast out the back of mine, that I very rarely have problems with soot accumulation on the bootlid/bumper. :)
 

Piranha

Veteran Member
Joined
Sep 12, 2003
Location
Malta (Europe)
TDI
golf 2000 Flash Red
I've got a 3 " on mine from the turbo back with 2 free flow mufflers.

space near the turbo is a little tight, but it's not that bad either
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
devonutopia said:
........I know the gas comes so fast out the back of mine, that I very rarely have problems with soot accumulation on the bootlid/bumper. :)
The fact that the "gas comes out so fast" is an indication that your exhaust could be less restrictive. If you made your exhaust tip 1 inch in diameter it would come out much faster yet (and probably make your boost higher).
 

SilverTDIGolf

Veteran Member
Joined
Oct 10, 2004
Location
Lower Mainland, BC, Canada.
TDI
2006 Golf GLS TDI
Personal preference. Some love the sound of an open exhaust from the turbo back, some prefer only to remove the muffler. I did it step by step. Tried the muffler removal, but eventually caved in and went with an open setup and was immidiately hooked on the sound it produces!
If you are looking for a lot of turbo whistle, the most noticable on my setup was after going to a straight through setup.
 

den9

Veteran Member
Joined
Apr 9, 2007
Location
doylestown pa
TDI
04 Jetta
i was thinkin a straight pipe all the way through wouldnt be enought back pressure. depending on the price ill get a straight pipe all the way back with a borla race muffler. unless someone can provide a sound clip of a straight pipe, besides that 4 inch one i seen earlier.

oh yeah what should i get 3 inch or 2.5 inch, i was thinkin 2.5 straight pipe or a 3 inch with a muffler
 

Whitbread

Vendor , w/Business number
Joined
Jan 21, 2007
Location
Johannesburg, MI
TDI
Several
I'll go take a couple pics and a movie clip of my set up with straight 2.25" and 2.5" muffler elimination. The less backpressure on a turbo diesel the better. The turbo will spool quicker and you'll have lower egt's. The sound did change a bit with the RC3+ Euro but you'll get the idea :), there no reason for a muffler at all unless you have vehicle inspections. I have zero drone with my set up.
 
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velociT

Top Post Dawg
Joined
May 10, 2006
Location
Not Austin, TX
TDI
06 Jetta TDI *sold*
Has anyone just punched out their cats to achieve the straight pipe sound? Trying to figure out whether i need to have straight pipes welded up or if I can unbolt, punch out, and reconnect.
 

Whitbread

Vendor , w/Business number
Joined
Jan 21, 2007
Location
Johannesburg, MI
TDI
Several
I just punched it out due to offset inlets and not wanting to mess with bends and straight pipe. Just cut it open on the conical part of the inlet or outlet, B.F.-Hammer and chisel it, then weld it closed. Presto!


 

den9

Veteran Member
Joined
Apr 9, 2007
Location
doylestown pa
TDI
04 Jetta
would it be possible to save the stock exhaust and cat, just in case its easier to sell it in the future, or maybe if future emissions require cats
 

LNXGUY

Top Post Dawg
Joined
Jan 10, 2004
Location
Barrie, Ont, Canada
TDI
'05 Jetta TDI Wagon
den9 said:
i was thinkin a straight pipe all the way through wouldnt be enought back pressure. depending on the price ill get a straight pipe all the way back with a borla race muffler. unless someone can provide a sound clip of a straight pipe, besides that 4 inch one i seen earlier.

oh yeah what should i get 3 inch or 2.5 inch, i was thinkin 2.5 straight pipe or a 3 inch with a muffler
Back pressure on a turbo car? The less back pressure the better....
 

REDNECKDZL

Veteran Member
Joined
Sep 1, 2006
Location
Omemee
TDI
2001 Jetta, 2015 Jetta, 1984 Wabbit TD, 1986 RX7 waiting on AHU swap
I'm running 2.5" cat back straight. I think it's worht while keeping the cat in since it's the only emissions thing on these cars and it doesn't do much for a power gain, if you remove it.
 

01tdiJEtt

Well-known member
Joined
Nov 7, 2006
Location
Loretto,Ont. Canada
TDI
2001 Jetta TDI
Anyone running turboback with a side exit? if so i really would love to see some pics. i'm thinking of running a 2.5in turboback with exit either on the side before the rear wheel or just a turn down. any thoughts?
 

mkosem

Veteran Member
Joined
Jun 27, 2003
Location
OH, US
TDI
2001 Golf TDi
I know GHL makes a side exit exhaust, and a TDI downpipe. There's bound to be someone running it :)

--Matt
 

Crazy Memphis

Veteran Member
Joined
May 30, 2007
Location
Canada, Québec, Montreal
TDI
VW Jetta TDI 2000
den9 said:
i want to do an exhaust on my jetta but im not sure what to get. whats the stock pipe diameter and should i do a full pipe from the cat back or just take the muffler off and add a tip?
the original dimention is 2". i made the modification to full 2.5" stait pipe and its really cool.... i made the mod. from the starting flenge down to the end. you can hear the spoiling of the turbo and it give you a small 2-3 hp more.
 

02DslPwr

Veteran Member
Joined
Dec 20, 2004
Location
Leander Texas
TDI
2002 Jetta Wagon, TDI
FWIW, here in Texas, Diesels do not have emmissions testing, they are exempt, just a safety inspection. This sealed the deal on a non-cat downpipe, ordering mine very soon.

I loved getting a $12 bill for my inspection rather than a $35 bill. Over a $20 savings per year on inspection, the savings just keep mounting!

Gotta love the TDI!

Robert
2002 Jetta Wagon
PP357
VNT-17
 

den9

Veteran Member
Joined
Apr 9, 2007
Location
doylestown pa
TDI
04 Jetta
mkosem said:
I know GHL makes a side exit exhaust, and a TDI downpipe. There's bound to be someone running it :)

--Matt
is it for the tdi? i never seen any good performance parts for diesels except injectors and chips
 

1.9TDI60MPG

Member
Joined
Jan 16, 2018
Location
Canada
TDI
2006 1.9 TDI
I just did a 2.25" pipe after the flex pipe out the side. The turbo can be heard at idle and it sounds very good but it sounds horrible when I get on the throttle, the turbo doesn't whistle it screeches, especially when cruising at highway speeds....could this indicate a bad turbo or will a 3" downpipe removing the flex pipe fix this?
 

Theguy1084

Member
Joined
Mar 30, 2018
Location
Charleston, SC
TDI
2006 Jetta TDI
I just did a 2.25" pipe after the flex pipe out the side. The turbo can be heard at idle and it sounds very good but it sounds horrible when I get on the throttle, the turbo doesn't whistle it screeches, especially when cruising at highway speeds....could this indicate a bad turbo or will a 3" downpipe removing the flex pipe fix this?
Check for exhaust leaks.

This post was 10 years old!
 

h4vok

Veteran Member
Joined
Feb 4, 2017
Location
Denver (ex MN)
TDI
2003 Jetta TDi 5sp 171k
I just did a 2.25" pipe after the flex pipe out the side. The turbo can be heard at idle and it sounds very good but it sounds horrible when I get on the throttle, the turbo doesn't whistle it screeches, especially when cruising at highway speeds....could this indicate a bad turbo or will a 3" downpipe removing the flex pipe fix this?
I have a turbo back straight pipe using as much of the stock pipe as possible. I do not have any weird noises. Mine has a different turbo than yours, but it should be nice and quiet even on the throttle. The turbo should be making whistle and whooshing noises not "screeching".
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
I just did a 2.25" pipe after the flex pipe out the side. The turbo can be heard at idle and it sounds very good but it sounds horrible when I get on the throttle, the turbo doesn't whistle it screeches, especially when cruising at highway speeds....could this indicate a bad turbo or will a 3" downpipe removing the flex pipe fix this?
Check your VNT vanes for proper operation and check the gasket on the downpipe to turbo connection - that thing will sound horrible if it gets to vibrating. Picture below is not exactly like yours, but you'll get the idea...

 

1.9TDI60MPG

Member
Joined
Jan 16, 2018
Location
Canada
TDI
2006 1.9 TDI
Thanks a bunch guys....will check that out...I just noticed that when cruising down the highway the screeching noise acts up along with my boost....if I cruise at 65 mph I have 5 pounds of boost and 50 mpg, then I hear the horrible screeching and boost goes up to 10psi and fuel economy goes to around 40mpg or so....turbo sounds sweet at idle
 
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