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4 - 1 Exhaust header install

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Exhaust header install

Target: Spdweb.net 1999 Honda Civic
Products: Polished stainless steal 4-1 header with farris metal plates
Purchased from ssautochrome.com

Things you need to know.

You will need a good set of wrenches, a socket set and a good torque wrench to complete this install. Before you start, MAKE SURE YOU HAVE ALL THE GASKETS YOU NEED! If your car has two oxygen sensors, (one before and one after the CAT) an o2 simulator is needed in place of the second o2 sensor if you plan to remove the CAT. If your car only has a single primary o2 sensor make sure your header has a threaded port to reinstall it. Your car WILL NOT RUN without it's primary o2 sensor. Your car will still run with no secondary o2 sensor however, the CEL will come on and your car WILL lack power.

I am using no CAT and do have a o2 simulator installed on my car. More information on o2 simulators including where to buy one can be found by clicking here.

Getting started

Remove the heat shield from the top of the existing manifold. Make sure you do not damage the primary o2 sensor. Don't worry if the bolts break off, you will not need them.

Remove the two spring bolts holding the manifold piping to the exhaust system. These to break easily and you do need to reuse them, most auto parts stores should have them in stock. After the manifold pipe is free from the exhaust, remove the bolts holding the pipe to the cast manifold (shown on a d16y7, Z6, A6, and y8 motors vary slightly).

Next remove the nine nuts holding the manifold to the engine head. Be sure to remove the manifold gasket, it is NOT re useable. Never try to reuse any compressed metal gaskets.

Notice the size of the exhaust ports in this picture compared to the pictures below.

A few words about efficiency

These pictures show the restrictive nature of the stock exhaust manifold. The picture on the left shows how small the inside diameter of the exhaust runners are compared to the ports in the head.

The manifold piping is another bottle neck. On the left is the stock piping, note the inside diameter of the pipe compared to the after market header on the right.

o2 Sensor advice

When handling your o2 sensors, be careful not to bump or even touch the sensors end. Doing so can contaminate the end and give a false reading once installed.

Be sure to properly install your o2 sensor in the new header.

Final nuts and bolts

Now all that's left to do is install the header. Make sure you consult the litterateur for your car and use the correct toque on the header bolts going into the engine head. Be sure not to over tighten them, since the studs are in aluminum they have an tendency to strip easily and cause major damage rather quickly. If you do happen to strip a stud that is going into your engine all is not lost. A rethread kit can be installed to quickly cure the problem.

Once installed and heated your header may turn colors. This is a normal reaction to heat, if you run hard enough you might even start to see some blue and purple develop. I also recommend replacing your stock mid pipe after the install this will help exhaust flow even freer through the system.