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dmp 09-20-2008 12:21 PM

DIY: DownPipe Install
8 Attachment(s)
I initially balked at the idea for fear of rusty, scary bolts and nuts. But, thanks to a lift, and all tools I needed, the install went very well - 2 hours, even with me stopping to joke around and chat with friends there.

First I removed the heat shield. More bolts there (10mm) than on the turbo/downpipe itself. None were hard to reach. Along the passenger's side, there's one down there - a small wrench had it off easy. Feel around the casing and you'll be able to remove the heat shield from the top after you find the nuts (6 or 8 I think).

Three 14mm bolts hold down the TIMC - there are two off the turbo, and one on the upper right of the IC. Channel-lock pliers help the hose come off the BOV, and a screw driver to release the hose clamp around the intake inlet elbow thing.

Now that the IC is out of the way, you'll see two bolts/nuts there on top, with a bracket. Those are 14MM as well - loosen those, then find the nuts on either side. Reaching your hand around it's possible to remove all the bolts on the DP/Turbo from the top.

As an aside, sprayed them down the night before with PB Blaster. They were so easy to come off, I was shocked - just torqued nicely, no worries.

Now, get under the car. There are two brackets holding on the stock piece, on up near the trans, and another down on/near the cat. They are 14mm as well. Only the one near the cat will be re-used. While you are there use a 22 open end to loosen and remove the O2 sensor.

Where that pipe connects to the y-pipe, there are spring-nut things. On the nut side it's a 12MM, on the other side it's a 14. The way mine were angled I used a 14mm socket one and a 12mm wrench on the driver's side, and a 14mm wrench w/ a 12mm socket on the passenger's side.

When everything was off, I had a friend use a pry bar a bit to move the pipe off the bracket near the O2 sensor. Once that got bent a little the whole thing came down.

Compare - see what the WG opens into on the OEM? A metal plate. A wall.

As a pre-caution against the Invidia WG flapper-tapping, I grinded down near the top of the divorcer, to help ensure clearance.

The Happy Machine!

Just as easy, the new one went back up!

You can see the bracket towards the bottom there - down near where the two pipes are touching (but not yet lined up). That's the bracket we pried a bit to get the OEM pipe to drop. Also - there's one bolt you'll have to get from under - and you'll have to use a wrench. The way the pipe works, there's no clearance for a socket.

After everything was tightened up I took to grinding/trimming down the Heat shield. I WISH I had remembered to take a photo of it. I'll find a photo of a stock heatshield and mark where I cut it.

Now - everything is back together and I'm set! I get the whistling/chriping - makes me think there's an exhaust leak. But I'll work those out eventually. As far as sound? To me it sounds like a tractor now.


CapnJack 09-22-2008 07:16 PM

Good write up!

I see you have the limited addition Spec B waste gate flapper. :lol:

dmp 09-22-2008 07:52 PM

:D Thanks (the wheel is also larger in that pic, too - but nobody notices :( )


FASTONE 09-29-2008 01:10 PM

I have a question for you, can you drive a car with a dp and no tune to the tuners location, around 20 miles, i got a Cobb DP and waiting to get it installed

dmp 09-29-2008 01:19 PM

Sure thing. Just don't go crazy. If you're into OpenSource type tuning I suggest (WARNING: NO AFFILIATION other than BEING A CUSTOMER. Me suggesting folk GO to this site, and contact them in NOW WAY implicates me as a part of this BUSINESS) visiting


For the record - I STILL have a HORRIBLE exhaust leak at the junction tween the DP and the OEM exhaust. :( Going to give it one-more try before taking to a muffler shop.


Regal05LGT 09-29-2008 04:26 PM


Originally Posted by dmp (Post 2082009)
For the record - I STILL have a HORRIBLE exhaust leak at the junction tween the DP and the OEM exhaust. :( Going to give it one-more try before taking to a muffler shop.


Did you use any type of sealer? If not, try the permatex ultra copper, held every joint in my exhaust w/o leaks

dmp 09-29-2008 05:50 PM

Gonna try that next; thanks Regal.


GTkansan 09-29-2008 05:57 PM

Did you trim the lower section of the heatshield too? I couldnt figure a way to get it it trimmed and retain enough points to keep it from rattling, basically i didnt reinstall the lower section, which I think was a mistake and i may give it the ole college try.

dmp 09-29-2008 06:08 PM

I did trim it - I have 4 bolts in, IIRC. I'll take it out this weekend and get pics for ya, aight? So...check back. To date, no audible rattles. :)

BigBad 09-29-2008 07:40 PM

Nice writeup.

scoobydoobie 10-02-2008 12:49 PM

nice write up. Your car sounds like a tractor now? any other aftermarket pipes or just the DP?

rurouni_x 10-02-2008 01:58 PM

did you put the donut gasket back on to your DP-exhaust connection?

dmp 10-02-2008 02:28 PM

Thanks - Just the DP and an Exhaust leak where it meets the OEM Catback. :)

LOTS Of whistle, too - as I rev. REALLY like that sound; second only to a VTA EWG. :D

g2redgsr 10-11-2008 07:13 PM

heres my stupid question...what is the difference between the uppipe and dp? plz excuse my ignorance im new to turbos...

GTkansan 10-11-2008 08:02 PM

The UP goes form the exhaust manifold, and leads up and into the turbo. The downpipe (DP) comes out the backside of the turbo.

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