I installed my EL headers on Saturday so I thought I'd post up my procedure.
First up I removed my airbox and intake, this makes it a lot easier to get to the heat shield bolts and the nuts that hold the turbo and up-pipe. Also gives me access to the EGT sensor and the no3 coil pack bolt, which holds the bracket for the A/FR sensor lead.
Next up, intercooler off.
First off, when working on the exhausts, it very important for everything to be cold, not just so you don't burn yourself, but also because when its still warm, nuts, bolts and studs are all expanded from the heat, I guarantee you will strip every nut you touch. I also soak every nut, bolt and stud in upper engine cleaner, it is the best penetrating spray out.
I removed the heat shields on the exhaust manifold, to allow me to get to the manifold nuts, and the bolts to the up-pipe. A little trick I use is to cut a slot in the right hand heat shield through to the hole where the A/FR sensor is located. That way you can remove the heat shield without removing the sensor, which can be a bitch to undo in the car.
Manifold off. It is nessacary to unbolt the manifold from the up-pipe, as it wont come down past the cylinder head. Don't forget to unplug the sensor and loosen off the no3 coil pack bolt so you can remove the bracket that holds the lead. Nothing worse then undoing the manifold bolts, going to remove the manifold, and still being plugged in.
With the manifold removed it is a lot easier to get to the sump, which I needed to change to a late model one to fit the EL headers.
Sump off. Its much easier to do if you undo the pitching rod on top of the box, and undo the engine mounts and jack the engine up.
First time I've seen the insides of my old girl, not to bad, nothing in the sump.
New sump and pick-up,which is also completely different. As is the dipstick.
New sump fitted, very nice.
Dump pipe off, the front sensor is my wideband. This needs to come off to allow easy access to the rear turbo bolt, plus the rear mounting bolt for the up-pipe. I then undid the other 2 turbo bolts and the front up-pipe bolt. You can try and get the up-pipe out from up top, but I find with turbo still there its pretty difficult. So with the engine still jacked up slide it out the bottom past the head, on my bugeye I had to loosen the EGT sensor to get it past the front sub frame.
Kunigawa TD06/20g
Install is reverse, fit EGT sensor to new up-pipe, slide in, and line up studs with mounts and turbo. I found the studs supplied very good quality, although the rearmost mounting stud is too long, it would definitely stop a standard dump-pipe fitting back onto the turbo, so I would grind it down before I fitted the pipe, if I did it again. Lucky for me my dump pipe has quite a big concave relief at the bottom of the turbine flange.
Next up, I removed the A/FR sensor from the factory manifold, I had soaked it in upper engine cleaner while I was doing other stuff like the sump, so it came undone easily, I fitted it to the new headers.
Then I loosened off the links that hold the 2 halves of the headers together, and, using the new gaskets supplied, fitted them onto the head studs. It's important to not do them up at this stage, just whack a nut on each side to stop them falling, then you can align the flange for the up-pipe. Put the 3 bolts for the up-pipe in, once again, don't tighten them, just a few threads. This is all for alignment, so everything slips on nicely without putting excessive tension on anything, Now I did up the head nuts, then the up-pipe bolts. Fit is nearly factory perfect, very impressed.
Very shiny!
Don't forget to refill the engine with oil, I only use genuine Subaru 5w-30 fully synthetic of course.
That's it then, all fitted, the difference in driving the car is amazing, so much more responsive! It used to fall into a bit of a torque hole coming out of corners if I was taking it easy, not any more, I love it.
The trade off is it sounds like a Hyundai with a milo tin muffler, but I don't care, its worth it for the added response, and its quite clearly a WRX.
I'd come up with a revised fuel map, but I need to log more data and make some more tweaks to it, now I've got these on.
Lastly, thanks to Wayne (JDM-STYLE) for organizing the GB on these headers, one of the best mods I've done so far, worth every cent.