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No pics.. not much to show. Easy job, just time consuming the first time.

Summary: Don't be scared to do this simple job. It was one of the most simple jobs I've ever done. I've done V6 timing belts and full suspension, and this was far easier than any of it. When I put the stock back on for smogs every 2 years, i will prob have the swap down to under an hour.

I removed the upper heat sheild a couple days ago so that shaves some time off the start of the job. That task takes about 10 mins at most. I did not remove my intercooler to get the heatsheild out.

The work tonight was very straightforward. I waited until the car was cool. I sprayed the 5 top bolts on the main flange with WD-40. I then easily broke all those 5 nuts/bolts loose with no issue, they came off like new. (Car has 60k miles). Removed the 5 top bolts completely.

Next I had to see what all the other connections looked like. I next removed one 10mm heatsheild bolt. You can see it from the engine compartment down the side of the stock downpipe.

I then moved under the car after jacking it up with a stand under the passenger side of subframe. There are two 14mm bolts attaching the stock downpipe to the car, I did not know about the upper one. You will see one up near the cat itself. The other is the "hangar" bolt people talk about. The hangar has a hook on it so you can hang the pipe while you set it up. I removed both those 14mm bolts.

Finally, I removed the two downpipe-to-catback spring bolts which came off fairly easy. I then unplugged the O2 sensor harness plug and unsnapped the holdowns so it could come out with the stock downpipe.

On install:

The Cobb downpipe looked a lot better than all the pics I have seen. The finish looked more shiny/stainless rather than the ceramic type surface I have seen in some pics. It was also a lot bigger in person than i expected in piping size.

The Cobb did not come with ANYTHING but the pipe. So I reused the gaskets on each side. I might order a new donut for when i bring it back stock someday for smog.

I put the new pipe in from under the car, and hung it on the turbo studs. I then attached the "hook" hangar for it to rest on. I went to top and started all 5 master nuts/bolts, did not tighten. I then put in the hook bolt lightly also. You do NOT use the other upper 14mm mid bolt with this downpipe. Finally, I attached the spring bolts which was the hardest part. I had to use channel locks to get it close enough to get the bolts started. Then I tightened everything carefully. As a last step I screwed in my O2 sensor and tie wrapped the harness nicely.

I then installed my Cobb stage 2 map which I will test tomorrow, been storming here.

Notes:

The donut which connects the downpipe to catback is very tight fit over the downpipe. Both stock and Cobb. I had to pry it carefully off the stock one with a large flathead. Make sure you install the donut on the new pipe before you install it under car. I forgot and it was much harder under the car to get it on all the way.

I would order the 2 gaskets in preparation if your downpipe does not come with them. It's a nice thing to have for emergencies.

I will be ordering a Cobb heatsheild also just to help out on heat.

I can get a few pics later of it installed if anyone really needs to see pics.
 

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I drove it to Starbucks and tested it a little bit. I have the normal new exhaust smell which I expected. One helpful tip to prevent that was washing my hands after the stock DP removal before I touched the new DP. Dishwash soap broke down all the oils on my hands very well, so less fingerprints got on the DP.

Comparing
stock ---> stage 1
vs
stage 1 ---> stage 2

I feel that there was a lot more noticable power going from stage 1 to stage 2. I didn't notice this much change when i did stock to stage 1. So as simple as going to stage 2 is shown in this writeup, especially if you already own an accessport.. you have to do it.

I am having temptations to do the Cobb catback next to just complete my setup end to end. But I like super quiet and stealth, so I might regret it. The only reason I would get a Cobb catback is just so I would "know" I had a complete Cobb system. Maybe in the future...

And I doubt I will keep this car longer than 2 years. I bought it at 59,500 miles. I've only had the car about 3 months. At that time I will remove my Cobb DP and accessport and sell it, Cobb has good resale value.
 

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I have the Cobb TBE and if you like the stealth factor than you can use your original turbo heat shield with the Cobb DP there are directions on the last page I believe on where to cut to make it fit and then that way when you pop your hood no one will know unless they are really familiar with the car. And if you do want that extra bit of sound the Cobb CBE is one of the quieter exhausts that you will find
 

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I have the Cobb TBE and if you like the stealth factor than you can use your original turbo heat shield with the Cobb DP there are directions on the last page I believe on where to cut to make it fit and then that way when you pop your hood no one will know unless they are really familiar with the car. And if you do want that extra bit of sound the Cobb CBE is one of the quieter exhausts that you will find
I won't be cutting my heat shield. Everything will be back bone stock when i sell it someday. I already have a Cobb heatshield on order.

I been thinking about a cat back, but i gotta take a month break after spending all that money.
 

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Thats cool well let me know how you like that new heat shield personally I like performance and quality more than looks and if the new Cobb turbo heat shield looks like it will keep things cooler than the OEM one does it will be something I might look into.
 

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Installed the Cobb heatshield this morning. Straight out of the box it doesnt fit very well. It hits the wastegate rod. But after some simple pressure and slight bending, it becomes a perfect fit. I used 3 stock bolts to attach it.
 

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Discussion Starter #7 (Edited)
Instead of making a new thread, I figured I'd just add to this one. Since most people thinking about a downpipe might be interested in uppipes also.

I installed my Invidia uppipe this morning. It came with 5 uninstalled studs, and a EGT bung. You can buy M10x1.25 nuts in order to install your studs ahead of time. The job took a good 4 hours. I already had a Cobb downpipe installed, so at least that's easier to remove than stock.

Install thoughts:

Just as hard as everyone says, huge pain in the ass. Not because of the physical tasks, but because of things that can go wrong.

I did NOT notch out my "O2 sensor cover" like some people do. I didn't need to. My O2 sensor socket fit on it and broke it loose easily. I removed it and then the lower shield fell off.

I didn't realize at first that I needed to unbolt that header section. One bolt seized up, but it was loose enough to swivel. Then it tightened back up ok. It is right under the uppipe preventing it from coming out. Even after I jacked the engine up an inch, I still had to remove that small header section to get the stock uppipe out. (Total of 5 bolts/nuts.) I used an air impact gun to remove the engine mount nut, otherwise it would have rounded off.

The EGT sensor looks exactly like an O2 sensor. I used the M12x1.25 bolt in the EGT bung hole to plug it up.

I used new gaskets and doughnut except for the header piece which I hadn't planned on unbolting. I am keeping my old gaskets in case one breaks in a later job.

I don't know if I would do this job again.

Results:

I did not expect this much difference. It was VERY noticable. It seems to me this is just as much of a butt gain as when I did my downpipe, maybe even more.. I did get stage 2 Cobb after my downpipe was installed. This feels like a lot of lower end gains rather than highs. I felt the difference right when I took off from a stop. This was a very worthwhile mod, although it was no fun during the work. I hope I am almost to stock STI levels now, the car sure feels fast.

Sidenote: Running stock airbox. Stock catback.
 

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Congrats! :thumbup: I am coming up on three years with the Cobb DP.
 

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Congrats! :thumbup: I am coming up on three years with the Cobb DP.
i checked out your mod list, its huge. I kind of want to stay stock springs as i like comfort a lot. I havent tested if this power is too much for stock springs yet.
 

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i checked out your mod list, its huge. I kind of want to stay stock springs as i like comfort a lot. I havent tested if this power is too much for stock springs yet.
Engine power and springs are really not related. Springs are all about handing. Once you go stiff you will not want to go back - makes the WRX a different animal.
 

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Once you go stiff you will not want to go back
amen to that ;)

And on the spring issue, I have to agree, as well :)
I went mildly stiffer than OE WRX (02), choosing Tanabe DF210s on stock struts. a little stiffer, but still comfortable to me. And yes, it handles decently, with a mild drop in ride-height..

Good write-up on the DIYs. :thumbup:
 

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Engine power and springs are really not related. Springs are all about handing.
I don't know if I'd say that they're not related. With springs that weren't made for that much power, you'll get a lot more squat out of them when flooring it. That adversely affects handling since it loads up the suspension of the car in ways it wasn't designed to be. I would just say that springs and HP are not closely related.
 

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great write up. i will be doing all of those tasks fairly soon (i hope). one thing to add though; for the price of new gaskets it would be extremely wise to not reuse old ones. any real mechanic will tell you its not worth the possible headaches to reuse the old ones. exhaust and other high temp gaskets are made to be compressed once and fill the imperfections in the mated surface. they are not designed to be reused. spend the extra few bucks and get new gaskets.

i will note that the donut gasket is a different animal, perhaps someone else could shed some light on the re-usability of that particular item.
 

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great write up. i will be doing all of those tasks fairly soon (i hope). one thing to add though; for the price of new gaskets it would be extremely wise to not reuse old ones. any real mechanic will tell you its not worth the possible headaches to reuse the old ones. exhaust and other high temp gaskets are made to be compressed once and fill the imperfections in the mated surface. they are not designed to be reused. spend the extra few bucks and get new gaskets.

i will note that the donut gasket is a different animal, perhaps someone else could shed some light on the re-usability of that particular item.
I spent $40+ on gaskets alone. Including the dounut. I just wasnt expecting to need those other gaskets.
 
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