How to Install Headers on a Honda Prelude 1993

Replacing the Honda Prelude's stock exhaust manifold with a header is a common high-performance modification. The stock manifold is designed for quiet operation; therefore, it is much more restrictive than an exhaust header. Installing a header can greatly enhance fuel efficiency and power, although the header is noticeably louder than the stock manifold. Installing a header on a 1993 Prelude is relatively simple, since the stock exhaust manifold is located at the front of the engine. Because the Prelude's exhaust manifold and header actually consist of two pieces, the two pieces must be separately removed and installed.

Difficulty: Moderately Easy

Instructions

Things You'll Need:

• Wrench
• Header gaskets

1. Disconnect the bottom of the stock exhaust manifold from the exhaust pipe. The exhaust manifold attaches to the exhaust pipe with two bolts underneath the engine. Remove the two bolts with a wrench. Then pull the exhaust pipe away from the exhaust manifold.

2. Disconnect the top of the lower half of the exhaust manifold from the bottom of the upper half of the exhaust manifold. The lower half of the manifold attaches to the upper half with two bolts. Remove the two bolts with a wrench. Then pull the lower half away from underneath the vehicle.

3. Disconnect the upper half of the exhaust manifold from the side of the cylinder head. The manifold attaches to the cylinder head with nine bolts. Remove the bolts with a wrench. Lift the manifold away from the cylinder head.

4. Connect the lower half of the exhaust header to the exhaust pipe from underneath the vehicle. The lower half must be inserted into the engine compartment from underneath the vehicle. A single header gasket must be inserted between the flange on the end of the header and the flange on the tip of the exhaust pipe. Install and tighten the two bolts which hold the lower half of the header to the exhaust pipe with a wrench.

5. Install the upper half of the exhaust header to the top of the lower half of the exhaust header. Place a single header gasket onto the top of the lower half of the header. Then lower the upper half of the header onto the lower half. Install and tighten the two bolts which hold the upper and lower halves together.

6. Connect the upper half of the header to the cylinder head. A single header gasket must be inserted between the mating surface of the cylinder head and the mating surface of the header. Install and tighten each of the header's nine retaining bolts to secure the header to the cylinder head and to complete the installation.

References

• Honda and Acura Performance Handbook; Mike Ancas; 1999