Now is when the real fun begins. Basically, from this step until the turbo is completely installed, the car will be undrivable. Make sure that you have the time and all of the supplies necessary to complete the job.
I am going to skip the specifics of the preliminary steps because I assume that you know enough to raise and support the car safely and disconnect the negative battery terminal before starting any of this!
Start by removing the lateral member in order to access the y-pipe. Unbolt the y-pipe from the headers (or stock manifolds if you don't have headers), and then from the cat. Don't forget to unplug the O2 sensor in the y-pipe if you have a '97. Remove the y-pipe from the hangers and put it aside. Unbolt the headers/exhaust manifolds from the block and place aside. For specifics on the removal, see the Header Installation Page.
I took Hotshot headers off of the
car only to put another set of Hotshot's on in their place. The newer style Hotshot
has a slip-fit collector connection where the older style has a 3-bolt flange collector
(see photo). The turbo uses the flange-type header collector so I had to replace my
newer headers with the older version. After installing both types, I have to admit
that the flange-type collector is much better than the slip fit.
The actual header installation is exactly the same as on the Header Installation Page so please see that for reference. There were some slight problems with the installation of the older version headers however. First, I had to have a crack in one of the headers repaired prior to install. Also, since none of the exhaust piping was coated, except for the original ceramic on the headers, I coated everything; headers, collectors, and downpipe, with TechLine's Black Satin.
Lastly, and most important, the
EGR fitting on the headers for the '93 cars is substantially larger than the fitting on my
'97. Because of this, I simply blocked off the EGR connection all together.
This is probably a good idea at the moment anyway since the car is not yet
intercooled. The EGR would simply pump already heated air back into the intake
manifold. This is certainly not a good idea in strict emission-controlled areas.
As you can see, I used a simple 5/8" brass flare plug to block off the
EGR bung in the header. I put a little Ultra Copper RTV around it prior to threading
it in to help seal off any leaks. An NPT threaded plug would fit much better than a
flare, but this is all I was able to find.
I also had to block off the EGR return into the intake manifold. I used the same type plug and also RTV'd around it prior to the threading it in the block. This makes the install much easier since one of the most difficult things to do on the header install was to bend the EGR tube correctly.
Don't forget to insert the O2 sensors in both headers and then simply install the headers and tighten them both down.