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Discussion Starter #1 (Edited)
While doing some reading up on installing my headers I found that there really wasn't a comprehensive thread that covered everything. I figured this would be a good writeup todo and give something back to the forum. I did the best I could to explain everything clearly and tried to get some good pictures but please feel free to add if you feel the need to.

First off there are basically 2 different ways to go about this. You can remove the intake manifold and radiator for easier access to the manifolds or you can just leave them on and work with the room you have. Everybody is going to have different opinions here and what you do will really depend on your experience with removing those items or personal preference. I chose to leave those items on because I haven't yet removed/installed either and didn't want to open another whole can of worms.

Now that I've said that I'll start off with some of the tools you'll need for this install. Here's a picture of everything I used.

The PB Blaster, swiveling rachet attachment and duel 6inch extensions were worth their weight in gold for this project. PB Blaster is penetrating oil that will help loosen seized bolts for those of you that didn't know.

The first thing I did was soak as many of the bolts that I could get to with PB Blaster right off the bat. This included the crossmember bolts as that will have to come off as well. Some of them were fairly easy and probably didn't need it but why not make it as easy as possible to get them loosened right?

I then removed both heat shields for the exhaust manifolds (1 on each side). To get these off you need to remove 3 nuts (2 on top and 1 on the bottom).

I then moved underneath the car and took some of the bolts for the splash gaurd off. It's not necessary to completely remove the splash gaurd. Removing a few so that it hangs down a bit will work fine to make some working room.

Next came the crossmember. To get this off there are 3 large bolts on each side of the car. They are on with a good amount of torque so pull out your large breaker bar or torque wrench to get these out. In my case the crossmember was stuck on. A few taps on the side of it with a small hammer and it hit me right in the face. BE PREPARED:muhaha:

I figured out that it's a whole lot easier to take off the y-pipe first to make access to the manifolds a bit easier. First I removed the O2 sensors on each side. I was lucky enough to not have them seized up. For this task I used the adjustable crescent wrench. Then I moved onto the big stuff. This is where the duel 6in extensions come in useful. To get the connections from the y-pipe to the manifolds put the two extensions together and use your breaker bar. This will put your socket wrench below the level of the piping giving you plenty of room to get leverage on those seized bolts. After getting those 6 nuts off (3 for each side) you can move on to the connection with the catalytic convertor. These will most likely be the most difficult to break free so don't hesitate to spray these down with PB Blaster multiple times and let them soak for 30-45minutes. I also used the duel 6in extensions on these to give me a bit more room for leverage. It took propping my feet on one of the tires and giving it everything to break these loose so expect a battle. Here's a picture once I got the y-pipe off looking at the cat.

The y-pipe has the hangers so having something like a block of wood for the cat to rest on is a good idea. As you can see my cat is in need of replacement and towards the top of my priority list.

The next picture is looking upward at the bottom of the exhaust manifold exit.


Here's a picutre of the stock y-pipe off compared to the new SSautochrome headers.

This is one of the reasons I got headers before a catback. The y-pipe (specifically the flex portion) is on it's last legs and starting to leak at both ends.

Now that we've got the got the y-pipe off we can get much better access to the manifolds. Each manifold has 5 bolts and 2 nuts on studs. The nuts on studs are located on the top of the manifold in the center. It is fairly common to have at least one seized nut on the thread. Then when you loosen it the whole stud comes out. When this happened to me I just kept the nut on the stud and used it the same way I would a bolt so don't worry about trying to remove the nut from the stud.
REAR: I found the rear easier to get to and remove but others will state just the opposite, again just personal preferences. To remove the rear bolts and nuts I reached in from the top passenger side of the car and tried to see/felt for the top half of the manifold with the exception of the bolt all the way to the drivers side, this bolt is much easier to reach from the bottom of the car. The bottom half of the bolts were reachable from the bottom as well.
FRONT: I found the front more difficult because of the tight space. Although, the bolts and nuts are much easier to see. This procedure is the same as the rear. I found the swivel attachment extremely useful here.

Here's a picture with the exhaust manifold off. Also shows the 2 studs in the middle and holes on the outside for bolts.


Whew take a break everything has been removed. Grab a beer, sandwich, catnap, etc. A good chunk of the hard work is done.

Back to work this isn't gonna finish itself! Use a wire brush to clean all the mating surfaces. Some of the old gaskets can be pressed on and require a screwdriver to peel off a corner but be careful not to damage the mating surface in any way that could cause leaks.

Here's a picture with the old rusted stuff. Bleh!


Here's some pictures of the new shiny stuff. MMMM sexy.


The kit comes with all gaskets and hardware to replace the old except bolts and nuts for the actual manifolds. I used high temperature RTV Gasket sealant on both sides of the actual gasket. I did this for 2 reasons: 1 I want to do everything possible reduce the chances of leaks and 2 it's tacky and holds itself to the surface. Put a small bead of the RTV around the outside of the gasket surface and inbetween each port opening. It will only go on one way and have all the holes line up. Figure out which way it goes and stick it on.

Now replacing the manifolds:
Front: I started with the front so choose the header with the EGR connector and carefully line up the holes so it rests on the studs. An extra set of hands is extremely useful to hold it in place while you put the first couple of bolts in. Put all bolts and nuts in finger tight then tighten them starting in the middle and working outwards to either side.

Rear: Repeat same process as front. With the rear you have to make a decision whether or not you're going to keep the EGR (Exhaust Gas Recirculation) tube or plug both ends. As far as I know plugging the EGR will not throw a CEL but will decrease gas mileage very slightly. I personally chose to plug mine because in the future I plan on either the ZE intake manifold or possibly the MMI when it's released. To plug mine I cut the old threads off the old EGR tube with a hacksaw (they are freely on the EGR tube not solid). I then cleaned them, filed the inside with a rough file, and made deeper striations with a screwdriver. The reason I did that was because I used JB weld in the stick form to plug them and wanted to give it something to grab onto. I have read of others welding a penny over it or something similar but I did not have access to that so I used the JB weld.

Next replace the O2 sensors front and rear. I've since read that you can use brake cleaner to clean these up a bit. I used a wire brush that seemed to help some.

Here's a pic of the front header on.

Tucked in there ever so nicely. Make sure to wipe down the headers to remove as many finger prints as possible before you fire the engine. Gloves help to reduce them to begin with.

Continued...
 

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Discussion Starter #2
Next the replacement y-pipe. Use the RTV gasket sealant again on the gaskets for the y-pipe/manifold connection and for the y-pipe/catalytic convertor connection. Stick them on and then you don't have to worry about them. Getting everything to line up was a wrestling match and it took some force to make them participate. The best advice I can give is to leave the y-pipe off the hangers until after you've got it bolted up. I found it easiest to get the nuts at the cat threaded on just slightly and then thread one nut at a time for each of the y-pipe/manifold connections. Once you've got one nut on each connection add the rest and tighten down progressively (don't tighten one connection down all the way then move on, tighten one a bit then tighten the next a bit between all three connections). I then put a screwdriver through the rubber hanger and pulled them over to the y-pipe hangers. Some WD-40 will help them slide on/off.

Here's a pic from below the car of the y-pipe successfully bolted up.


Double and triple check all bolts...

If you removed the IM and radiator now you can put them back on. Otherwise replace the splash gaurd, cross member, and anything else you took off. Now the part you've been waiting for. STARTER' UP!

It's normal for the pipes to smoke a bit for the first heat cycle and I actually had a CEL for the first drive. I haven't had one since. Figure it was probably the extra gasket sealant burning off. It's also normal for the pipes to turn a goldish color from the heat.

Happier car finished shot...

Dog not included...

Well I hope this enormously long write-up helped someone else out there complete the process. Yes, it is a PITA but will end up saving you a ton of money from paying to have it done at a shop. Let's hear some feedback...

metros
 

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damn good write up! karma for ya. most ppl probably wouldnt attempt header installs by themselves but your writeup will help alot:tup: PM one of the mods and they should make this a sticky in the projects thread.

quick question though: what is the exit diameter of the y-pipe just before the cat?
 

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Discussion Starter #4
Thanks and thanks for reading that monster of a post! Off the top of my hand I don't know for sure. I never thought to measure that while in the process. Hopefully one of the mods see's the post and approves of it enough to make it a sticky without me asking them to.

metros
 
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