How to make 3" exhaust?

[Integrale]

Hello

I working on the exhaust on my Q4, does anyone have a picture of where the best pat is for a 3" exhaust system? I hope to have 3" FROM TURBO and all the way back. The tricky part is out from turbo and past engine sump.

Leif

[mpampis_]

http://i157.photobucket.com/albums/t79/mpamphnos/ee88dced.jpg
http://i157.photobucket.com/albums/t79/mpamphnos/83eade5f.jpg

take a look mine

[Brul(tm)]

This is how the exhaust custom made under my Q4.
http://i115.photobucket.com/albums/n288/BrulTM/EPS%20march%202003/IM002930.jpg
http://i115.photobucket.com/albums/n288/BrulTM/EPS%20march%202003/IM002932.jpg
http://i115.photobucket.com/albums/n288/BrulTM/EPS%20march%202003/IM002956.jpg
http://i115.photobucket.com/albums/n288/BrulTM/EPS%20march%202003/IM002957.jpg

The downpipe is the original one whitout the first kat.
I do't have any pictures of those adjustments.
The exhaust manifold is original and is one of the things that is going to need attention.

Back box, smallest and quite open.
http://i115.photobucket.com/albums/n288/BrulTM/EPS%20march%202003/IM002941.jpg
http://i115.photobucket.com/albums/n288/BrulTM/EPS%20march%202003/IM002938.jpg


Regards,
Marc

[Integrale]

Thanks both, this give me a idea how to do it. Marc is yours 3"? Its hard to se on the picture.

[Brul(tm)]

Thanks both, this give me a idea how to do it. Marc is yours 3"? Its hard to se on the picture.

http://i115.photobucket.com/albums/n288/BrulTM/EPS%20march%202003/IM002944.jpg

Yes it is ;)

Regards,
Marc

[Integrale]

Very nice work Marc, I will try to do it like yours. Its importend that its not to mutch nois, and yours is ok as I understand-

Leif

[jimnielsen]

you can make the entire first section from 3 x 3" 90 mandrel bends. It is possible to get the exhaust very close to the underside of the car this way.

1. weld the vband clamp or what ever you are using to attach the 3" bend to the turbo outlet.

2. attach the first bend to the turbo outlet.

3. workout the angles for the 2nd and third bends from the end point of the first.

4. tack weld them into place.

5. remove the whole thing, weld, then take it to an exhaust place and have a slip coupling made on the final end of bend 3.


6. job done.

I see from your pic of your turbo that you are using a vband clamp... This makes it much easier because you can simply weld the flange onto the start of the first 90 degree bend, attach it to the turbo with the clamp and rotate it so that it comes as close to the engine as you need.

You need to make the final bend rest against the side of the lower cross member and sit right against the viscous coupler. This ensures that the exhaust is not the lowest point of the car.

As far as noise is concerned, my exhaust is configured like Marc's with just a single 'straight through' muffler at the very rear. It makes very little noise as compared to non-turbo race cars and has no problems with the 75db limit we have here for noise..

[Integrale]

Nice picture, I see you manage to straigthen it out nicely around the engine sump. The picture I posted was only for illustration, because i dident have my laptop with the 155 pictures on (but it is almost the same turbo). The exhaust flens is "standar" for 2,5" so I have to use a reducer into the turbo.

Here are picture of mine

[Brul(tm)]

Its importend that its not to mutch nois, and yours is ok as I understand-

Leif

The setup as it is now is quite noisy.
I don't have the previous two boxes only the last back box. After removing the first cat in the down pipe it became a bit louder. I like the sound, very low and dark :thumbsup:

I had a couple of warnings at the track to take it easy in the acces tunnel :lol:

Regards,
Marc

[Integrale]

Ok, so its a good idea to have one silencer in front. I think I have to anyway to get the car approved.

[Integrale]

Then I started to weld my 3" exhaust. Comment if you do see anything wrong, please :ninja:

[jimnielsen]

you are off to a good start! can we see it from underneath?

[Integrale]

Haven't done anything today, but here are some picture under neath. Need some more pipes, flexpips and one silencer :driving-014: