Well, other than a few scratches on my hands and some aching muscles (I need to exercise more...) I have fitted the extractors (and cat back system) without any real probs.
For those of you thinking about doing it, here are some instructions and photos.
Stock Manifold:
First, I removed the leads (I was replacing them as part of my servicing), engine cover, air intake cover and maf pipe. Also, from under the car I removed the nuts attaching the manifolds to the engine y-pipe and oxy sensors (remember to unplug them first). There is one more nut to undo on the passenger side, which I think is the EGR or similar. At this stage the manifolds are ready to be removed.
Undo the lock nuts first, noting where the clips for the spark plug leads were fastened. Then start loosening the manifold bolts (they look like nuts on studs but the whole stud comes out). The rear driver side bolt was very difficult to access, so best to start with that one, so that you are not stuck with one stubborn bolt. Carefully lift the manifolds up and out of the engine bay without scratching anything. I noticed mine did not have any manifold gasket and I would be interested if this is the same for all models.....
At this point you need to remove the engine pipe/cat from the rest of the system, or else you cannot pass the extractors down through the space between the engine and the inner guard. Only two nuts so it doesn't take long.
Extractors:
I did not receive any instructions with my extractors so I was not sure if I should have installed gaskets. I did not have them with me so I left them out (no leaks so far!!).
Also, if you have them welded to the engine pipe (the y-piece that includes the catalytic converter), you can never remove them as they need to be remove from the top, so I cut a couple of slots in the flange, and used u-bolts to fix them in place. Note there may be a tendancy for the flange to close in on the hacksaw if you do this, but it makes later removal so much easier.
Carefully pass the extractors down into the engine bay and line up the manifold with the cyliner head, having a bolt in one hand ready to screw into place to hold the extractors. Start returning all bolts but leave loose until they are all in, as there seems to be a lot of play until they are all in. Start tightening evenly until ready to torque.
Engine y-pipe modification:
Now the only tricky bit! You need to temporarily bolt the cat back onto the exhaust system, to work out where to cut it. You will notice by the photos that a lot of pipe is removed, including the support posts (note mine is a manual so an auto might be slightly different??). Once bolted loosely into place, lift the y-pipe up so it is level with the extractors, and mark it with a marker texta, sufficient so the pipes will push through the entire flange on the end of the extractor.
Use an angle grinder with a metal cutting blade and wear eye/ear protection. I reckon you would be there a long time with a hacksaw but if you don't have an angle grinder it may need to do. File all the cut ends to ensure there are no sharp edges or burrs that may make installation difficult. Also, make sure you remove any filings that could clog the cat converter.
Final installation:
Under the car, slide the cut ends into the flanges of the extractors. There may be a chance they do not align perfectly, so either find a mate to work on one side while you are on the other, or I wrapped an ocky-strap around the extractor pipes just to pull them in enough to align with the y-pipe. With a bit of convincing they should slide into the flange so that the cat can be bolted back into the exhaust system.
Refit the oxygen sensors into the extractors and screw in the egr pipe. Replace all leads and maf pipe etc, in reverse of the removal.
Start the car up and allow the oils and surface paint to burn off (there may be a lot of smoke...). Then after a final check to see all is tight, you are done!
In my case I fitted the cat back system that I had removed a while ago, which only requires two bolts where it joins the Y-pipe, plus 4 retaining clips that hold the hanger rubbers in place.
I am sure it is not my imagination that it has a little more bottom end, but the best part is the growl from about 2800rpm!
If anyone knows if gaskets should be installed, let me know!!.
Good luck!
How to install extractors (ecotec V6)
![[MR SS]'s Avatar](http://forums.justcommodores.com.au/./customavatars/avatar24315_2.gif){kind=avatar}
My Ride
Linear Mode
