B5 – Removing DP’s to make Piggies (For 6spd)

  B5, DIY

This DIY can also be referenced for:
1. How to remove Oxygen sensors
2. How to remove Passenger side EGT sensor

Note: This DIY is for 6 speed dp removal. For you tip guys it is more difficult to remove them and I hear you have to drop the sub frame a little to make room to slide the DP’s out.

First things first:

Disclaimer: The modification described in this article is for OFF ROAD use only. It may render your vehicle non-street legal. Use at your own risk. I assume no responsibility for you performing this modification to your car.

I guess I’m just covering my butt by putting that disclaimer in. I dont mean to scare anyone so basically to each his own.

Anyway, MODS – feel free to move this post to a better place, or even make a sticky if you feel it worthy.

I took on the project of removing downpipes to make them into piggies myself. I was excited to do this, but at the same time nervous because I didnt want to get into something I couldnt finish.

A few notables:
The hardest part that basically brought me to a halt in the project yesterday was the rusted clamp bolts holding the dp to the rear exhaust. I just didnt have the right tool to cut them off.

I wasted a lot of time with much furstration to the point of almost punting and giving up. But then I asked around and found a friend willing to borrow me their grinder. Then it was a piece of cake.

I had heard the heat shields were the hardest part of this project, but to me they werent bad at all. I had the misconception that you have to take heat shields off before taking dp’s off. This is not true, I dont think its even possible. Just unscrew them and leave them in there loose and the dp’s will slide down under the heat shields.

I know there is a write up but I thought I’d give a little insight to how I approached it

List of tools needed:
Jack stands
straight and phillips screw driver
ratchet and various extensions
13mm socket
17 mm socket
5 mm allen socket
6 mm allen socket
3 or 4 foot pipe to put over ratchet for leverage (mine is called the motivator)
pry bar
vice (strongly recommended )
wire brush for cleaning up inside of precat.
grinder with cutting wheel, or torch for exhaust clamps

extra’s you might need to borrow or buy:
22 mm 0xygen sensor socket ($9.99 – autozone)
good size drill bit (I would make sure its sharp)

I’ll make sure and add more when I reinstall the dp’s if I missed anything.

Parts needed:
4 new 2 and 1/4 exhaust clamps – 2.50 a piece
4 spark plug defoulers (I bought from advanced autoparts – used 2 per cat) the 17mm kind there is post on second page with pic showing what part number and kind to get.
Best part about these defoulers is price – $8.38 for all 4

1. Took off air box and plastic tube that goes to y pipe. (I left y pipe in place. Didnt see need to take it off)

1.5 Disconnected plastic pipe between Y pipe and air box. On 2001 models like mine and newer, this plastic pipe has a breather connected to brake booster (I think that is where it goes to) Anyway this can be a little tricky to take off, but use a screw driver to pry from bottom of connector and press with your thumb from inside and it will pop off. I was affraid of it busting off, but if you are gentle but firm it will come apart. (thanks Jerbal[Jordan] for insight on getting this piece off)

2. Unscrew antifreeze overfill tank and moved it out of the way – take off sensor on bottom.

3. Removed passenger side egt valve from dp. (I think 17mm wrench is what I used) to get the egt loose, I hooked another larger wrench to end of 17mm wrench for more leverage, this made it easy to get loose. I wrapped EGT in plastic to protect head.
You see EGT in center of this picture:

4. take 2 bolts off both heat shields (You can see the two holes for heat shield in above pic) – (5 mm allen) important to use right allen because I could see these being stripped and much more of a pain if you do that. Do this for both sides.
5. remove o2 sensors from both sides (22mm o2 sensor socket is a must) I bought the socket from autozone for 10 bucks. Both were real easy to take out once broke loose. I was able to remove with fingers once loose.
Below pic shows O2 socket on passenger side O2:

Below Pic shows extensions and ratchet on Passenger side O2 – NOTE – I also put a 3 FT pipe over ratchet for leverage to break O2 loose. (Not pictured) Be careful not too push too hard so you dont strip anything or litterally break it. More leverage is great for loosening nuts and bolts, but also make it way easier to strip or break things if not seated correctly, or using wrong size socket.

This one is of driver side heat shield, you can see left allen easy, and part of right allen, then down you can see hole for 02 but have to look hard to see it.

6. Now I jacked up the car and put it on jack stands. Had emercency brake on. Then left the jack in place as a 3rd support for safety.

7. Next I crawled under the car (wishing I had a lift) and started on bottom side Woops forgot the right socket up on bench. Had to crawl out
Got wrench then crawled back (still wishing I had a lift) Dang now I forgot the flashlight, crawled out again. I bet I did that 30 times. Such a pain
Anyway, try and bring all the tools you need so you dont have to go back and forth so much.

8. With the car jacked up, what I would do next is work on the clamps that hold the dp’s to the exhaust. (I didn’t do this next, but in hindsight it would of been the smart thing to do. If they look rusted at all, dont bother trying to unscrew, just get a grinder with cutting wheel and grind the clamps off. Or a torch will work too. If you dont have either, stop working and go buy one or find a buddy with one, because you will waste too much time and get no where except to get more frustrated.
Once clamps are off, leave sleeves on loosly that hold the dp’s to rear exhaust so dp’s dont hang.

9. Now you have to take the shield off above the front drive shafts. These are held on by 3 – 6mm allen screws. The side ones are easy, but the ones up on top is a little bit of a pain, but if you get some long extensions you can get the top one off with a little patience and determination.

Here is a pic of it in place from underneath:

Here is a pic of it out on the floor so you can see the 3 scew locations I think this is drivers side cover:

10. With the cover for front drive axle off, you can see the bolts for dp’s to the turbo’s real easy. Take the bottom 3 bolts off holding the dp to the turbo (17mm wrench) Mine were real easy to loosen, once they were broke loose, i just unscrewed with fingers.
Pic of drivers side turbo from underneath after dp removed:

Pic of passenger side turbo from underneath after dp removed:

11. Now there is a metal hanger that is spring loaded holding dp’s to car. Unscrew this and take off (13mm socket)

12. Next there is a hose clamp holding the bottom of the heat shield to the dp. take straight screw driver and loosen and slide off heat shield -No pic of this.

13. Now take the rear O2 Sensors out of main cats. Remember to mark which side is which so you know where to put them back in. Again you’ll use the O2 sensor socket, these are easier to get to. In pic below it shows the O2 with the new Defoulers in place already, but its a good pic to show where they are located:

14. Now slide sleaves off holding the dp to the rear exhaust and the rear of the dp will fall to floor.
Repeat pic but you see the sleaves/clamp holding dp and rear exhaust – just slide it towards back and dp will drop:

14.3 Now if memory serves me right, your ready to wiggle the dp’s out of car. They might not look like they will come out. But with enough twisting and movement, they will.

14.5 – after the dp’s are out its a good chance to reach up from bottom of car and feel the turbines for the turbo’s for play in the shaft. At least thats what I did. There was little play, but felt solid and spun freely.

14.7 With both cats out, you can start drilling:

15. Before you start, make sure you put a mask on:
Ok ok, yes I look like a geek, but my wife came out of house and quick grabbed the camera because she said I looked funny. Ah… she loves me.

Also be sure and have plenty of ventilation, I went and got a fan (not pictured) and had all doors open. This stuff is pretty toxic.

16. Now some guys say cut the precat apart, then knock it out, then weld it back. Well I dont have a welder and I heard you can do it just fine without cutting it apart, so I started gutting it through the flange. The longer Cat is def easier then the shorter cat because the angle of the flange is more of a direct angle to the cone inside.

16.5 Make sure and have the cat held up so the inside materials fall foward out the hole and not drop down and get caught in the main cat. (Notice picture of me again, you can see it propped up in background)

17. Now find the longest drill bit you can(I would go with 1/2 or 3/4 inch if possible), and drill a number of holes into the center of the thing. My bit wasnt very big (no side comments) Anyway I tried to make one in center, then 4 around it. Also make sure the drill bit is sharp. I heard some guys say they got the bit stuck and couldnt get it out. I had no problems. It drilled through it real easy it was a new bit.

I bought a small pry bar for 3.50 from menards, this is what I used to punch the stuffing out. It worked good, but wish it didnt have an angle at the end, would of been nicer to have a bar that was more straight. A little longer bar would of been nice too.

18. I worked on getting a center of the cat cut out, this way I could pry the sides away from the wall of the precat:

19. So finally it was all gutted out:

Here is the insides in a bucket:

It took me probably about an hour to drill and pound out 1 cat (I did longer easier one first)
The shorter one took me hour and a half.

I recommend to frequently take the cat out of vice and shake the loose stuff in a bucket so it keeps it clear and also less chance of getting any down to main cat. But shouldnt be a problem with main cat propped up in the air.

20. Once gutted out you need to clean the sides so there is no loose particles. I spent some time working on both cats because I wanted the sides as clean as possible. I knew I was close to getting it done and back on road so I had to fight the tendancy to say “good enough” and put it back in. Be sure and take your time and get it clean so loose particles dont float down to main cats.
I bought a 3″ wirebrush wheel and attached it to a long skinny extension. I bought both parts from Menards was 7-8 bucks for both. It was kind of cobbled together but it worked for me. The 3″ wire brush barely fit in the flanges of the cat’s but they did fit. Just make sure the wirebrush wheel is attached tightly to the extension otherwise it could come off inside the cat and that would make it hard to get out. I didnt have a problem
Pic of contraption I made up:

Here is pic of sides all cleaned up:

21. I next fit the Sparkplug non foulers into the rear O2 sensor locations. I doubled them up on each side. the shorter defouler goes into cat, then longer defouler into the shorter defouler (hope that doesnt confuse you)
Reason for this is you need to screw the O2 into the longer defouler. because the other one is too short and wont reach the threads of the 02.
Note: Some O2’s may not work in these defoulers because of how long the sensor part is. I had the factory ones and they barely screwed in, in fact it was only being held on by a few threads. But it was tight so I just used them this way. You may want to try drilling the holes out of the defouler so the O2 can fit in there all the way.
Best part: NO CEL and NO CODES

22. Once you have the defoulers in place you can start putting it back together!
What I did was fed dp’s through openings to turbo’s. For me the drivers side was the hardest, so i slid this one in back first. With a little twisting it went right through opening. (If it gest stuck, back it out and keep turning it different ways to find the easiest path.) I just pushed the heat shields up a little and flanges slid right under heat shields. I thought I would have to drop sub frame but didnt need to. Went through easier then I thought.
I then fed the passenger side through. Did same thing.
I hung each dp on the 4 bolts for the turbo’s (basically back in place)

23. I then went to rear of DP and slid the sleaves in place to connect dp to rear exhaust to just hold in place.

24. I then went back to front of dp and screwed 3 bottom bolts on turbo’s for both sides.

25. I then went to top side of car and screwed the 1 top bolt onto turbo’s for bothsides. Then took 17mm wrench and tightened all bolts on both turbo’s.

26. I then stayed on top (engine bay) and put O2’s and passenger side EGT back in. Screwed down head shields (5mm allen), put air box back in, coolant tank.

27. Once everything on top was done, I went under car again an I put the hose clamps back on the bottom part of the heat shields attaching them to dp. I thought of leaving these off, but I didnt want any rattling so I tightened them down.

28. I next put drive shaft shields back on. (Personally I was tempted to leave these off, but I figured they are there for a purpose so put them back on. I did only use the 2 bolts per side and left the top bolt off. They were snug so I felt they were held on good enough. 6mm allen (Again you will want to use your own decision on this)

29. Now you can tighten the spring loaded hangers 13mm socket that hold dp to car. I think these are used to help support dp so all weight isnt on turbo??? Not sure.

30. Now you can put the rear O2’s back in, again its 22mm O2 socket.

31. Now put new clamps on sleaves holding dp to rear exhaust.

32. You should be done! But now the most important step:
Check your work and make sure you didnt forget something!!!
I did this somewhat, but didnt look thouroughly and forgot I loosened some sensor that plugged into the engine on top by passenger side heat shield You can see the thing in this pic: its circled in green

Anyway you can see I loosened the screws but didnt tighten. Well this caused my car to drip oil (it was funny all week I seen a little puddle each day, but it was small and just thought my car was starting to leak now – to my dismay)

Well I didnt tighten this up and when I took it for a drive, the car ran fine but after I got home I noticed smoke coming from engine. I then saw oil on ground and dripping at a good rate on passenger side, kind of by turbo (YIKES)

I put it up on jacks and saw it all oily from under turbo (YIKES YIKES)

then I cleaned up up, and started car again and saw that these bolts were loose and it was dripping from what ever thing that is. (Phew)

I tighted that thing up, and now it runs like a champ. So moral of story, MAKE SURE AND CHECK OVER EVERYTHING!!!

It took me about a week in my spare time. You could probably get it done in a day following my handy dandy instructions lol

Here are a few random pics of the rear exhaust, sleeve and clamps I cut off. Any pics help:

Anyway I am proud that I was able to do this. It makes a world of difference when you have the right tools. If you dont have the right tools, then its better not to attempt this. And honestly I dont think it was that hard to do, just need to do things in the right process.

It may look daunting, but dont be afraid. Its much cheaper then buying the piggies from vast (I think they are $450 plus core) and for those of us “on a budget” as my wife reminds me of frequently this is the easy way to do it. Its also fun and such a great feeling of accomplishment.

I work in IT so have a desk job, but wrenching on cars isnt the hardest thing in the world, so I think if I can do it, anyone can.


Source: http://www.audizine.com/forum/showthread.php/231301-DIY-B5-S4-Removing-DP-s-to-make-Piggies-(For-6spd) – By gointoscot

One Reply to “B5 – Removing DP’s to make Piggies (For 6spd)”

  • How did you get your heat shields off. No one really explains that part I tried last night for 3 hours.


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