DIY: Uppipe install! Keeping your manifold and turbo in touch!
When you are trying to maximize your stock or upgraded stock size turbo the uppipe is another place to free/smooth your airflow through the exhaust. If you are replacing either your exhaust manifold or turbo you should definitely look into an uppipe, given these are two of the methods to replacing the uppipe.
If you follow the Subaru method for replacing an uppipe you will be removing the turbo and pulling it up through engine bay and out. I have never tried this method and have stuck to the tried and true exhaust manifold removal, followed by the uppipe coming out through the bottom.
Determined by your tools, mods and current exhaust setup this installation will greatly vary your install time. With the exhaust manifold method and my tools and skill level, I will spend around an hour on this mod. If this is your first time, be sure to give yourself extra time.
A few of the tools hat will help you, with links to the tools. Gearwrench ratcheting wrenches metric Milwaukee 3/8th impact Milwaukee 3/8th electric ratchet O2 sensor socket Gearwrench 3/8th extra long ratchet, 3/8th extensions 3/8th torque wrench Grey Pneumatic 3/8th socket set
We will start with top mount intercooler removal. Here is a link a complete DIY here and the quick version starts now. You can remove the downpipe without removing the intercooler, but if you need to remove the dogbone… You will need the Tmic removed. Locate the bolts/nuts that hold the bpv and intercooler down and remove those. Next will be the breather hoses removal and releasing the clamps from the turbo and throttle body.
Next you will need to remove the donwpipe. Full Diy linked here. Quick version starts now! You will need to remove the five bolts that attach it to the turbo and the two bolts that connect it to the midpipe. Lastly removing the transmission support bolt and taking the downpipe out.
With the downpipe out of the way you may now start loosening the uppipe to turbo nuts. Three connect to the turbo and two connect to the brackets that support both the turbo and uppipe to the engine. While you are up here you should disconnect the O2 sensor connection and bracket off the passenger side valve cover if you intend to leave it attached to the manifold.
Now if you are disconnecting the O2 from the manifold you will use your O2 socket to break it free or 22mm wrench. I find the large protective shield makes this difficult and use my O2 sensor socket. Set the O2 sensor somewhere safe to protect it. Oils from your hands or any damage to the sensor can cause an erratic reading and need to be replaced.
Having dealt with the O2 sensor you can now located the two bolts that connect the uppipe to the manifold and proceed with removal. Locating the six nuts that bolt the manifold to the heads is next on the list, I like to loosen them all and use a box to support it while it comes down. The large size and awkwardness of the manifold can make getting it down quite difficult.
With the manifold removed the uppipe will now just attached to the turbo and brackets on the upper side of the engine bay. If you are replacing an aftermarket uppipe you can leave the engine in place. If you are replacing the factory unit the heatshields are going to cause issues and either need to be trimmed/bent before removal, which can be difficult given its location in the engine bay. The second method being to remove the dogbone mount and loosen the engine mounts. Having all three loose/removed you can now use your jack and a piece of wood to move the engine up slightly. This gives you the much needed room to remove the factory uppipe. You may need to turn and contort your uppipe but it will come out after a bit of trial and error.
Having the old uppipe out you are now ready to install your new unit. Most aftermarket uppipes like the Grimmspeed unit shown here will easily slide in and out without moving the engine. This makes any removal later down the road much easier. Now you will place your new turbo gasket on and place the nuts on the studs to the uppipe to hold it in place.
Now we will slide the manifold back up into place with the new gaskets and once again with your hand attach all the nuts but do not tighten it down. You can now slide the bolts through the manifold and and uppipe once again just placing the nuts and uppipe together with your hand. There are many different ways to finish this install and you can use your favorite but this is my preferred method.
Start by running the nuts on the passenger side of the manifold up but not to your final torque value. Move to the driver’s side head and on to the manifold to uppipe. Lastly we will move back up to the top of the engine bay to snug up the turbo to uppipe bolts. This should help level everything out and you can now return in that order to torque all your nuts and bolts to their proper torque spec. Overtightening can warp flanges and cause leaks, be wary of this!
With all those bolts torqued you can torque the two left over bracket studs on the uppipe. And with everything lined up you should have a leak free preturbo exhaust system. You can now lower your engine back into place, torquing them down. Then on to the dog bone
I will state that some pieces will fit better than others and I have experienced problem parts that won’t seal with this method. It seems some uppipes and certain manifolds may just not work with one another given their angles/lengths, flatness of gasket area, etc. It can really be discouraging and I have had my own problem parts too. Another helper for these problems can be copper gasket sealer.
You can now lower your engine back into place, torquing them down. Then on to the dog bone back in place. On to the rest of the assembly with the O2 sensor going back home and on to the downpipe. Then back to the intercooler to finish everything up. Install walk-through for both the downpipe and intercooler for installation.
Now you can start your vehicle up and double check for any exhaust leaks. If all appears well you can lower the car down and take a short drive to double check that everything is working well. Many forum posts will tell you to recheck the torque after a week or two of driving as the expansion and contraction can loosen up the connections.
Congrats! You have completed the uppipe install! Now you can enjoying driving with a quicker spool or lack of cat to fall apart and take out your turbo!