Hey guys, first post here! I just installed skunk2 alpha headers onto my 2002 rsx type-s and I was having some difficulties that I believe others have had such as with fitment and other aspects of the install. Also couldn't find much on the topic really anywhere so I'm going to try to make this as detailed as possible
A few things you're going to want first:
A jack that can lift the car up at least 19" (may be able to do it with other jacks but I found 19" made it easy)
10mm-19mm sockets (cant quite remember which were needed, 12 & 14 were definitely the most used)
flex head ratchet (mainly for convenience)
Impact drill definitely helps
socket extractor set (in case you strip any or someone else did)
New exhaust manifold gasket
- May have to edit this list as I cant quite remember if this was everything
Getting the stock manifold off
First things first, after you've jacked the car up put it on jackstands you need to clean up the area you're working in a bit. Take the power steering line off with a 10mm socket (there are 2-3 bolts that need to come off) to allow for some more mobility behind your engine. You're going to need either a 12mm or 14mm socket/wrench to get 2 nuts and 3 bolts connecting the stock exhaust manifold to the head of the engine. Remove the old exhaust manifold gasket and clean the head a bit as well. All can be reached from the top of the engine/engine bay so there is no need to try to get it from under the car.
Next, you need to get under the car and start unbolting things from there. It doesn't exactly matter where you start unbolting things but I like to single out the area that I am working in so I took the Cat off from the rest of the exhaust. This requires removing 3 14mm bolts and be careful when you do this because something might drop down and hit you onto your head. After you have this removed you can continue taking off the manifold/cat combo. There is a bracket holding onto the cat that you may see, leave that for now and come back to that after everything else is off. This part may be slightly different for everyone, when removing the cat from the manifold there should be 2 spring bolts (may be regular bolts or something else, may differ from car to car hence the difference) that need to be removed with either a 12mm or 14mm (some trial and error may be required for that depending on what you have there) if these bolts break don't worry you shouldn't need them as your header should have all the necessary material. Now go back to the bracket from earlier and remove the bolt holding the header to it with a 14mm (again i cant remember completely) and everything will more or less come falling out so just watch your head.
More stuff under the car
A few things you should do while also under your car at this point are removing your swaybar at the 4 bolt which I believe were a 17mm socket. This will cause the swaybar to swing downwards so again watch your head. You should also notice that you have some play with the swaybar, pretty sure that's normal but don't quote me on that and do some research on swaybars and endlinks because this is focused on the header. That bracket holding the cat? Grind it out, you wont be able to have any headers with those in as far as I know. You should also check for basic maintenance things while under here but its not necessary
Getting your header in
Little side note; you may have to grind/cut away the hanger piece on the header it self, attempt with it and if it doesn't work then do without it
Now comes the hard part... not really
People have been complaining that the fitment is garbage and complaining about everything about these headers but they probably didnt have any help or just didnt try the methods I'm going to list for you below. And a little side note keep your adapter piece off for this time because it just makes it harder.. or dont, im just a random poster not a cop.
Try the Third method below first, this is what i did and it worked like a charm
First method I have seen: remove the swaybar completely and connect it after (or don't use one at all)
Now this method works and gives you a lot of space but honestly isn't worth all the hassle and anger of trying to get the swaybar back in. Essentially you just remove the swaybar from the endlinks using an Allan key and a wrench and then pop the header up with all the play you get from it
Second method: Remove the oil filter
Like the first method this has you doing some things that you probably dont need to do but hey to each their own. Obviously you're gonna have to remove the oil filter and deal with all of that nonsense but it should give you enough wiggle room to get the header up into the bay and in a good spot for the sway bar.
The Third and last method that I haven't seen or just couldn't find is the easy method (easiest for me at least)
Zip tie your swaybar as high and as far back it can go, this is going to give you a good amount of space to work with and will allow the header to slide underneath it.
Put the header in sideways. Yes you read that right, sideways. Have the 4-tube facing the drivers side and the other end should be facing the passenger side. Slide it under the car and start angling it to where you want it to go. You may have to move your jack on the passenger side around slightly but thats fine because you're prepared. Then all thats left to do is get the header above the sub frame/resting on the sub frame and up where you need it to be. AS SOON AS YOU GET IT RESTING ON TOP OF THE SUB FRAME YOU HAVE COMPLETED THE HARDEST PART
Now all that's left to do is bolt the header up to the head, put on a new exhaust manifold gasket and then bolt the header up to the head with the 2 nuts and 3 bolts you removed earlier or with new ones (the thread is 10x1.25 40-45mm depends on a few things but you can always compare and grind it down if needed). Attach the adapter piece to the header with whatever 2 bolts and nuts that can fit (genuinely cant remember if we were given the nuts/bolts for this) and then bolt the adapter to your exhaust (does not have to be done this way, you can attach the adapter to the exhaust first). Torque the bolts and nuts at the head/header connection to 33 foot pounds and torque the bolts/nuts to 16 foot pounds where it connects to the exhaust (or just full send that bitch whatever floats your boat) and you should have your new header properly installed!
This install wasn't as bad as people make it out to be as long as you have some help and/or some guidance. It takes time and it will get you frustrated but thats to be expected from a 20 year old car. Also a lot of these steps can be used on other headers. Please let me know if I have forgotten something or made a mistake somewhere
Hope this helps!